They have also said not to hold your breath on that as Apple are notoriously slow in giving approval even if the relevant APIs were available. It’s been mentioned in the other thread - seeMy Sonos speaker bar, controlled by the Sonos app on my iPhone, can stream Apple Music independently. I hardly use it, though, as I use the Sonos bar only for TV viewing.
Additionally, Wiim indicated as of March 2022 that they are actively discussing with Apple the possibility of integrating Apple Music in the Wiim app. See screenshot of Wiim forum I attached to this post.
https://audiosciencereview.com/forum/index.php?threads/wiim-mini-streamer.31182/post-1324162
and subsequent comments