I keep adblock on for most sites because ads are so intrusive and often malware vectors. If advertisers want my eyes they need to not be obnoxious.
I started blocking YouTube ads in particular because it kept serving me ads that were brazenly homophobic ("how gross and smelly is gay sex? Find out!")
I feel no moral problem with this, if you do then your priorities are bad, IMO.
Edit: as a counter example, ubo doesn't seem to work on Twitch but I have never attempted to find a different solution as it has never run ads worse than the usual "lying about how good a product is" you always get with marketing. Further, I don't see them very often because the channels I watch the most I buy subscriptions.