Wiim amp bluetooth vs chromecast sound quality?

[WiiMer SJ]

While listening on apple music via chromecast from andriod device. Music sounds really compress. On the other hand casting via bluetooth source Apple music (AAC Code) on same scenarios. Music sounds different. It's having good quality. Details are present. Sounds fully open. So my question is why casting via chromecast sounds bad and bluetooth sounds good.

Given the fraught history of Alphabet and Apple it's a wonder they're interoperable at all. Where they do, it's due to motivated self interest or government mandate.