I can't think of any. But the thing is, but 4 years (after 2022) is not much, that's how long it took for Wikipedia to take off, most similar project I can think of: OpenStreetMap, Linux, GNU, arXiv... took longer than that. You can't judge success in 4 years.

After a quick search I stumbled upon Wikifunctions (2023), but do Wikimedia projects that are not Wikipedia count? A bit more controversial would be Anna's Archive (2022).

We have to think about the needs too. There was a need for an online encyclopedia, Wikipedia took it. What need do we have now that is currently unanswered and can be answered by a collaborative effort similar to Wikipedia?

Also, open source projects, so many come out every year that it is hard to count.