Just to add another not requested opinion...
During a long recover from a ski accident, I did compulsively comparisons among AMU and Tidal hi-fi, sometimes with some from free qobuz plan.
I set up to do instant switch, testing dozen of synced same song releases, without this, aural memory can easily lead to false impression.
Generally speaking, new releases don't have so much differences in sound charachtet, I think editors already give digital masters not needing further process.
With old file footage, especially from 70ies and 80ies, which are definitely digitized and frequently upsampled, Amazon generally tends to give 192khz and adds a sort of wider stereo image, with voices and guitars a little bit backwards. Tidal and Qobuz are more similar among them, in sound character and have less stereo "distance".
I can't absolutely say that Amazon is worst but it seems a little fake and results may vary.
Amazon has also variable sampling rate and results, even in the same album.
I decided to stay with Tidal hi-fi, for pricing reasons and (IMHO) better app. I don't understand why Amazon loose playing queue, while casting and Qobuz misses the "play similar song" button...