I think this is what confuses many people when they do their own tests, they don't know what to listen for and expect a more general sound quality difference over all parts of the recordings. The differences are actually in particular kinds of sounds, like high hats or piano, and only at specific moments, and only in specific music. For music that is all distortion all the time likely no one can tell the difference. Some people are irked at the slight changes in sound at specific moments compared to listening to CD's or vinyl, some don't even notice it because it is brief or those instruments/moments are not present in a particular recording.

Yeah, it's not a general loss of quality. He actually showed me a really cool YouTube video that explained what is lost with compression, where the person making the video played the same passage of a song compressed and uncompressed, and then showed visually the parts of the waveform that were clipped, and then played the clipped parts isolated. It was a lot of high-pitched, tinny noise, presumably from the upper end of the high hat cymbals and stuff. Wish I still had it handy.