You can use newpipe (find it on f-droid) as an alternative to the youtube app. It has some other benefits too. It seems to block ads as a side-effect. You can a

You can use newpipe (find it on f-droid) as an alternative to the youtube app. It has some other benefits too. It seems to block ads as a side-effect. You can also fix the stream quality. It has a few limitations too, but it's better than playing them in firefox, and even the youtube app for my use cases.