Ideally, good equipment that has been installed and placed properly should sound very good, to whatever extent it can. Room correction software like Audyssey, etc are for the people who can't or don't want to move things around in order to have better sound, so the goal from these is to make a 'bubble' where the sweet spot is larger. Does it work? Depends on a lot of things.
FWIW, I have a two channel system because the room really isn't good for surround and that removes the motivation to attempt it when the results are unlikely to be 'great'. However, I really like the sound and I have been working in audio for over 45 years, have heard some incredible equipment and was there before digital sources became available to consumers- some source material is good, some not so good and some just makes me smile.
Good timing for this thread- I was trying to figure out how to post a link for a song that I really like and have been playing often, in order to listen to all of the details. I'm using no equalization but I did place some panels in the room to fix some problems in the low end-