Difference Between Music Platforms Audio Quality to YouTube?

What is your listening environment?

Circa 2004 I listened to a CD of an album through good headphones and thought it sounded night and day better than the 128k mp3 files of that album I'd been listening to. That got me to upgrade the bit rate and I would say 192k mp3 is much better and 320k is much much better.

You really should use ABX testing to answer the question

https://theproaudiofiles.com/audio-perception-and-abx-testin...

but it does take good gear and a good environment to hear a difference. I encode AAC Pro files at 96 kb/sec for my watch which I think is fine for listening to music in a noisy gym, out on the trail, etc.

Spotify and Apple Music to me sound about the same. Amazon Music supports CD-quality audio minimum by default, which is nice. I think YouTube supports 24b/96k audio (or the video/audio-track equiv) assuming that's what the user uploads. The official record-company uploads to YouTube sound close to CD-quality but might not literally be.