Anecdotally: I use YouTube very rarely. I follow a couple of channels that post new episodes now and then. And sometimes I need to study some DIY technique, or someone sends me a link to something they thought was funny or interesting; basically my use is random and mostly utility-driven, and certainly not fueled by me endlessly trawling YT for entertainment.

So for me, the ads are super annoying because they steal time away from me when I need to access some random video, and ad-to-video ratio is rather huge. But since I'm a light user, it will never make sense to pay for it. In fact, I often close down a video when I'm met with an ad, because it's just not important enough. For me, the ads kill the potential spontaneous joy that could be had from a short video.

Many people do pay for YT, and I don't really understand the attraction unless you're a parent with kids. But everyone is different.