The term moderation itself often came from debate and discussion venues where moderators would police speeches.
This isn't true, it's just that the spatial constraints IRL mean there's never been a need to scale moderation of town squares beyond intuitive methods. Go to your physical town square and start screaming slurs and threats of violence at passers-by, and see how long it takes before the community "censors" you.
In developing and developed countries I've had (ostensibly) mentally ill people shouting epithets at passerbys and they're just ignored. So I think this is more about cultural norms.
Moreover, the case you mention is simple. If a spammer joins a forum and starts spamming, there's usually broad support to kick them out. Once the argument becomes ideological, that's when sentiment is a lot more mixed
No it wouldn't. As big as Facebook is, they still only moderate their own platform, and there is only one instance of Facebook. Separate vBulletin instances do not constitute a single, collective "vBulletin platform." The narrative of "Big Tech" as an organized leftist conspiracy orchestrating censorship over all social media is simply right-wing propaganda.
That's my point. The reason vBulletin forum moderators aren't equivalent to Big Tech censorship is that you can run your own vBulletin, independent of theirs. Censorship of Facebook is bad because that isn't an option.
Case in point: a number of Youtubers fed up with the platform demonetizing and delisting their content are advertising their content on other video platforms, or just hosting their own like Corridor Digital.
The web is one of the few examples of the free market actually working, but people have fallen for the defeatist and nihilistic narrative about the "centralization" of the web and "control" by sinister forces, insisting that competition with any big platform is simply impossible.
They said that about MySpace too and look what happened.