I disagree, yes; there can be a difference in the sound of a specific speaker and amps/receiver that are used together.
BUT, this is a BIG but, most mainstream, moderately efficient speakers, such as the Boston's or B&W's, will work with virtually every receiver on the market, and changing brands of receivers will not change the sound of these speakers.
So when is there a sound difference?
First:
It is the highly difficult speakers to drive, such as some electrostatic speakers and other exotic speakers, with resistances as low as 1 ohm, or resistances that bounce from one extreme to another, combined with highly inefficient designs, that are critical to match with the right amps.
These big, bad (and absolutely wonderful sounding) speakers are an absolute witch for most receivers, and a lot of amps as well.
Powering up a difficult speaker is not always solved by using a big wattage amp. Many smaller amps with really big power supplies, huge dynamic headroom, and ability to drive varying resistances as low as 1 ohm which are usually a better match for these difficult speakers.
(I just read a review where the reviewer was using a 15w tube amp to power Martin Logan electrostatics to ungodly volume levels... wattage isn’t everything, it is what you can do with those watts that is sometimes important)
Secondly:
It is the low efficiency, or modestly efficient, speakers, especially the lower resistance 4 ohm speakers, combined with room dynamics (size, shape, dampening) at high volume levels that seem to impact the sound of a receiver. This sound difference is most likely a byproduct of a low powered receiver that is approaching its clipping point, rather than a difference in the absolute sound of a brand of receiver. IMHO changing brands of receivers can make a difference in such a case, but that difference seems directly related to power supply and dynamic headroom of the receiver, rather than an absolute difference in the brands of receivers.
By the way, want to change the sound of your speakers? Play with your room acoustics....