Yeah nah buddy.
I only have YouTube Premium/Red because it came free with Play Music, then they killed that and we all jumped to Spotify because it was/is so much better and kept our subscription just for ad-free YouTube.
If they seperate YouTube from YouTube Music, YouTube Music would die in seconds. The app sucks, having it linked to YouTube sucks, they know this.
And in 5yrs you'll have watch a fullscreen ad before you can reply to a message.