rumble isn't any better. On podcasters with large following I still see the spam bots. I don't even read the comments much because of that problem.
The only solution is to setup the comments section where users have to pay money in order to comment. For example I should cost 21 sats or less for the first comment. After that it's free to comment. I can't see YouTube or Rumble implementing that.
But since nostr let's us build our own system on our own websites. Then you will have wait until someone releases that software and you can bypass YouTube and rumble.