YC companies can post non-votable submissions without comments advertising (yes) that they're hiring.
They fade down but since there's no voting obviously there's a different presumably mainly time (but perhaps also interaction?) based mechanism for that.
e.g. Avenue (YC W21) is on the front page at the moment:
https://news.ycombinator.com/item?id=27559764
It's at least not that new. Agree with you some seem to utilise the privilege a lot more than others, just anecdotally/by observation, but it's certainly not just Jerry (and Avenue).
