I am for sure one of the smaller number of people doing this, but I watch YouTube on my TV using the TV app. As a result I always had to watch ads. I wish I could avoid them. I suppose a could watch from an alternative and then AirPlay it to my TV, but that’s about it.
Not anymore, it used to. Pihole can only block ads that are served from known ad servers. But with the way ads are served on YT, it can't block them without also blocking the entire video.
My pi hole currently blocks around 10% of all the requests made on my network. So its still worthwhile for cutting down on some ads and tracking.