Recently, just from my youtube subscriptions I think, my youtube ads have been surprisingly relevant, for things like cnc routers or various embedded tools or what not -- ads that are actually for things I might be interested in buying. (Granted there's still a ton of obnoxious get rich quick schemes that I have to skip).
I have to admit, seeing ads that actually are of interest to me does change my mindset on advertising a little bit. I still find it super creepy being tracked, and I'd like the ability to know what they know about me, and erase it if I don't like it (is that even possible?), but it is kind of nice to get ads that don't suck if I have to sit through ads.