I see what you mean but I don’t agree. The deal being made here is obvious and you’re signing up to give them data in exchange for watching a video. You’re also signing up to view their ads. You have an option not to be the product at all. You already have the wheat, but you’re giving the middleman less than what was arranged, not just producing less.
And if you view it as okay to not give them what they’re asking for while getting the content anyways, that’s chill. Just recognize that you’re paying less for the content than they’re asking. This is even more enforced by YouTube and news papers who charge for ad free experiences.

It is, yes. It’s a separate conversation of if it should be illegal or immoral to keep your privacy this way. But as long as you are violating the intended method of revenue for the content you’re viewing, that’s piracy to me.
I think most people hear piracy and think it’s immoral or illegal, but there are very valid reasons to pirate content such as game and movie preservation.