Attention: I assume you know how to touch computers a moderate amount. This is literally just building the package, but that is because apple-music-bin is using the wrong electron. This leads to a problem: Widevine is missing. Guess what you need to run a proprietary music service.
Do you need to install Apple Music on Arch Linux? Do this in your terminal.
git clone https://github.com/Alex313031/apple-music-desktop yay -S nvm cd apple-music-desktop nvm install npm install npm run build sudo cp -R dist/linux-unpacked /usr/local/lib/apple-music sudo ln -s /usr/local/lib/apple-music /usr/local/bin/apple-music
People who give more of a shit than I do can go ahead and figure out how to PKGBUILD this, or alternatively how to fix the existing AUR package for this: https://aur.archlinux.org/packages/apple-music-bin