dang won't like me sharing this repo (sorry!) but hn-undocumented has a relevant section on this:

https://github.com/minimaxir/hacker-news-undocumented?tab=re...

> Currently, there is no evidence that non-job submissions about a YC startup receive preferential treatment on the front page, or kill submissions critical of a YC startup. In fact, the moderators have stated that they explicitly avoid killing controversial YC posts when possible.

And also:

> Additionally, founders of YC companies see each other's usernames show up in orange, which — although not an explicit benefit — does allow fellow YC founders to immediately identify one another in discussions.