If someone uploaded non adult content to one of the adult sites doing totally non-controversial things, like discussing smart phones or say a 20 part series on linear algebra, would they be kicked off the platform? Is there some effort to titillate requirement?

I'm imagining some vlogger doing an epic trolling email thread with the mods about how "actually, many people find e&m physics lectures erotic..."

PornHub have lots of non-NSFW contents -- they have no issue with that.

You just don't want NSFW ad popup when you view them.

I have no idea why porn sites wouldn't attempt to compete, their technology is solid, sometimes industry leading. Diversify.

I would also just like to remind everyone that there are many video sites out there that aren’t explicitly porn sites (but do generally allow some level of porn) that are not YouTube. They also tend to have NSFW / scammy ads as those are the only advertisers willing to pay to advertise next to content that wouldn’t be acceptable on YT.