The local subs are by nature ghost towns, and the first people to get them rolling will often establish some weird culture that will never be uprooted.

I disagree, though. The most over-moderated are any having to do with any product or service (especially particular websites or pieces of hardware or software), liberal-left subs, or subs related to any industries that are dominated by particular companies. This happens because companies make sure to control the modding of (what they consider) their own subs.

In the case of liberal-left subs, the Democratic Party has prioritized controlling all political discussion amongst the people whose votes it feels entitled to post-2016, when H. Clinton's campaign press released that it was assigning a budget of millions to "Correct the Record" anonymously online. In that year, the party apparatus was indistinguishable from Clinton's campaign organization, and those people continue to do the same thing except the budgets have gone way up. This was also when the Democrats and the CIA/FBI started to become mutual admiration societies (which I think has worn out to a certain extent after Gaza and ICE) but you can see how the personnel and tactics diffused over the past decade until their effects became overwhelming today.

Might be better to say that the local subs are the most organically over-moderated, but even then sometimes that first little clique that gets them rolling are actually connected in their local area, and engaging in the same kind of thoughtful, collaborative, profit-motivated manipulation as above.