On Android one can use ReVanced: https://revanced.app
Giving this another whirl. Tried Revanced a year(ish?) ago, but couldn't get it to actually work, so I've just been getting ad-free music the old fashioned way (yar!), but streaming again would be nice.
Edit-
No luck. I think the issue is I need the 7.20.51 version of YouTube Music, but that version doesn't appear to be compatible with my phone (Google Pixel 8); and trying to slap the patches on the current version doesn't stop the ads.
I'm probably the least techy person on Lemmy, so if any of you want to hold my hand through the set up, I'll happily take any help you're willing to give. Back to mp3's.