Articles critical of Airbnb, one of yc's biggest wins, also get flagged and taken down.
https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...
As those comments explain, this has been the #1 rule of HN moderation from the beginning. See also https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que....
I don't think anyone familiar with this community would assume positive bias towards Sam, Airbnb, or even YC anymore - it's quite the contrary, from my perspective, but of course everyone notices different things and has their own view. Ditto for political slants.
Like, I dont really expect puff pieces for ycombinator or the like to get artificially pushed to the top, but I do expect that enough people who are feel culturally or financially invested in ycombinator to flag negative things into oblivion, especially as its completely reasonable that the population of users here has a much higher percentage of those folk than any random population sampling.