I'd be more than happy to pay for HN, but I think it's a very bad example as it's not funded by any kind of ads/tracking (not directly at the very least).

The entire site is one giant ad for YC. The only difference is that HN has achieved an extremely effective content marketing strategy so tracking isn't needed.

It keeps a permanent list of your votes, comments, and submissions. It maintains your social credit score ("karma"). HN is absolutely tracking the hell out of you.

HN does have ads: they look like posts, but you can't vote or comment on them. They're job ads for YC companies.

You can see a list of recent ones at https://news.ycombinator.com/jobs

I'm not sure if I get the point of your question.

Not everything needs to be monetised (or directly monetised) to serve a purpose.

Too much.