uBlock Origin seems to block all advertising on Youtube for me, including pre-roll and intermission ads in the videos. The only advertising I see on youtube these days is the sponsored sections inserted by the video creators.

I don't really watch that much youtube but now that my son watches some cartoons on it I've subscribed to premium so he doesn't see any ads. I think it's ok to pay for youtube as it arguably provides a useful service. I also know that I'm in a privileged position to be able to pay for youtube premium, so my comment is not about whether ads are inherently bad or not, just that you can watch youtube without ads if you pay for it.

I also don't ever have to deal with ads - perhaps because I also have a (seldom used or visited) channel?