It really all boils down to how much of what you hear are soundwaves that come at your ears in a straight line, directly from the front of the speaker vs. how much of what you hear are soundwaves that reflected off of some surface in your room before they made their way to your eardrums
There's truly no "right" or "wrong" with this part of audio reproduction. No "standard" what-so-ever for any listener or speaker manufacturer to aim for. Measuring a speaker in an anechoic chamber completely eliminates the microphone capturing any reflected sound. The only sound being measured is the direct sound in an anechoic chamber. Thus, such measurements really cannot tell you how that speaker is going to sound to your ears in any given room from any given position within that room. You can measure the speaker in the chamber from every conceivable angle. With those measurements, you can see how much sound energy is being cast in any given direction and thus, make some educated guesses as to how much louder the direct sound will be vs. the reflected sound. But it really all boils down to the room.
That said, some speakers produce a dispersion pattern that is practically a lazer beam shooting straight out the front of the speaker. As in, if you measure that speaker in an anechoic chamber, when you have the microphone directly in front of the speaker, you might get, say, linear response at 89dB with the microphone 2 meters away and using 1 Watt of power. But move the microphone just 5 degrees off axis and the response gets way quieter and maybe the response is no longer linear with the high frequencies rolling off, for example. And the further you move off axis, the quieter and less linear the response becomes.
Such a speaker will always deliver considerably more direct sound vs. reflected sound to your ears, PROVIDED that you are sitting directly in front and on axis with the face of the speaker. Thus, you have a teeny tiny "sweet spot" where the direct sound is aimed right at you. But at all other angles, there's much less sound energy being cast out into the room, and thus, far weaker reflections off of any given surface.
So a speaker like that, to a fairly large degree, takes the room "out of the equation". Not entirely, of course, but you are hearing FAR more direct sound than reflected sound, so what you hear is more or less dependent solely on the frequency response of the speaker itself and rather independent of the room in which you place such speakers. But you've gotta be in that one, tiny sweet spot!
On the complete other side, you've got speakers where no matter what angle you measure them from in the anechoic chamber, they're casting out sound that is just as loud, or very nearly just as loud as when you are measuring the speaker straight on axis. With such a speaker, you can very reasonably predict that you're going to have much stronger reflections.
Now one benefit here is that no matter where you are sitting in relation to the speaker, the direct sound that comes in a straight line from the speaker to your ears is going to have very nearly the same frequency response as any other position. So the "sweet spot" is huge! Go ahead and sit pretty much anywhere, the direct sound is going to remain pretty much the same. BUT, you're going to have a lot more sound energy reaching your ears that is not direct. And all of that reflected sound is going to completely change the frequency response that your brain actually receives. Your brain is going to sum together the direct sound and the reflected sound, and there is going to be interference, both constructive (peaks) and destructive (dips) as well as differences in phase - and all of those interactions are going to change from seat to seat!
Now, all of those soundwave interactions are precisely how we get a sense of our bearings using auditory cues to figure out the shape and size of the space in which we're sitting. With no room reflections at all, we tend to feel very uneasy - even nauseated or panicked - because with no sense of our bearings, our instincts tell us that we are exposed and in danger and there is no protection nearby or an obvious route towards escape! But outside of an anechoic chamber, we don't need to worry about that
Back to speakers though, what you get - in very rough terms - with a highly directional speaker vs. a speaker that is closer to omni-directional is a speaker that "transports" you into an auditory "space" that is created by the speaker vs. a speaker that brings the instruments and performance "into your room", respectively.
With a highly directional speaker, you're relying on the sound cues included in the recording to "tell you where you are". If the recording was, say, made in a church or an auditorium, and the microphone picked up the reflected sounds of that recording space, with much more direct sound than reflected sound in your listening room, you're going to feel "transported" into that church or auditorium because the spatial cues you're hearing will be the ones in the recording. And those cues are saying you're in that big church with its characteristic echoes and other reflected sounds!
On the other hand, if you're only hearing direct sound and you're listening to a studio recording where the performers were close-mic'd and the microphone only picked up direct sound, now you have virtually no spatial cues at all! Now it sounds as though some disembodied voice is "coming out of nowhere", or perhaps, that the voice seems to be coming from "inside your head", directly between your ears - exactly like headphones, which are a perfect example of a playback system that is almost entirely direct sound with no room reflections at all!
Meanwhile, that same studio recording played back on omni-directional speakers is going to "bring the singer and instruments into your room". It's going to seem as though the performers are right there in front of you - like you've brought them into your room for a private performance! On the flip side though, that church recording is going to sound very diffuse, echoey and weird. You've got your room's own sound cues telling you you're in your room, but you've also got the recording's sound cues telling you you're in a church. Your brain tries to combine and process this conflicting information and the result comes out "fuzzy"
Now you don't really know where you are based on the sound cues, so it all just seems sort of "mushy" and indistinct.
So is one dispersion pattern "better" than the other? Nope. It all depends on what you're listening to and your room's acoustics! But
most people tend to favor something that falls somewhere in the middle: a fairly wide and even dispersion from the front surface of the speaker so that you get a fairly wide "sweet spot" and not a "lazer beam" of sound that makes everything sound like headphones, but a gradually decreasing output as you move further and further off axis so that you are getting considerably more direct sound than reflected sound. That way, the speaker itself is responsible for more of what you hear and it's a little more independent of the room. But the room isn't taken entirely out of the equation either.
But when you hear either extreme, it can be a fun and educational experience. Some folks hear that omni-directional sound - especially with a close-mic'd studio recording - and it just
does it for them because they really get that sense that the performers are
right there playing in front of them like a private concert! That can be a very compelling experience. On the flip side, maybe you'll hear an extremely directional electrostatic or line array speaker and be "transported" to a different place in a way that no other speaker has done for you before. The effect will only work for one person who is sitting perfectly still, but it too can be a very compelling experience!
There's no "right" or "wrong". And certainly no reason to question what you like! Most "typical" speakers simply fall somewhere in the middle, so that's what we're used to, and they're sort of a "jack of all trades". An omni-directional speaker will enhance certain recordings and detract from others is all. It all depends on the recording and your room's acoustics.
But it sort of makes a good case for having multiple listening systems so that you can experience your recordings in multiple ways! Match the playback system to the type of recording and your own personal taste. We should all be so lucky, eh?
