This may be controversial but YouTube ads are surely ones that meet all the reasonable criteria. They're not a surprise, you know it's an ad supported business. They're served from YouTube so it's not random companies tracking you while you use a different service. And you can get rid of them by paying for the service. What's the proposed alternative where you contribute for the service? Just paywall the whole thing?
The alternative might be Google paying their fair share of taxes. I might consider supporting their product then. Ad blocking is not as severe as tax avoidance though. I have no sympathy for the service. If it's not profitable, Google can cover it from their other revenue streams with ease.
Are you also boycotting every other large company that uses the tax system in a legal way that you don't agree with? I'm all for big companies paying their fair share, but I'm not blaming the company, I'm blaming the people in charge who don't close these loopholes. Same issue as with Ireland in the EU, undercutting all the other EU countries with tax rates.
One option if you want to fight back in the exact same way: Sign up for YouTube Premium through a cheaper country and pay $2/month instead of 15.