Fun, I thought my sentence would trigger the pro-ad people, not the other side.
I don't think there is any legal definition of "piracy" (except for ships). My own definition of piracy is "accessing content without paying the official fee". Here "official fee" is the ad. Also, it can be seen as equivalent to DDoS, since you are voluntarily using Google's cloud resources while breaching their EULA.
Personally, when using newpipe, I do feel like I'm stealing unrightfully bandwidth from Google, though the price for that bandwidth is definitely not worth a tenth of the ads Google show me.
