I do not disagree that tactics like "building viral interest" may happen here (not necessarily by mods or with their help though), as they happen also in reddit

I do not disagree that tactics like "building viral interest" may happen here (not necessarily by mods or with their help though), as they happen also in reddit, as OP shows, and in general obviously all around the internet, and it is safe to assume that it does happen from time to time. For me the most disturbing part of the post is that the manipulating tactics target teenagers. But talking about repressive behaviour by mods against YC-related criticism specifically, I do not see that. I understand the prior would be that a popular forum run by YC would want to protect and censor in order to protect interests of the companies they back. I also had that prior. However, this is not "occam's razor", it is a prior. The time I have been around here I have not noticed this kind of behaviour happening though, while I have definitely noticed other kinds of stuff getting repressed, meaning that it is less likely that such repression would go unnoticed all the time. Thus I adjusted my understanding accordingly by shifting the prior according the data. If you find different examples I am willing to take them into account.