>Meta decided that the revenue wasn't worth the compliance burden, so they do not accept any political advertising at all

Obviously, Meta's most important revenue stream comes from scam advertisements, so all other ads are expendable.

As far as I know, political ads just must be labelled as such and there are some other small restrictions. Definitely not something that is hard for meta to implement, if they wanted to. But I admit that fines are very severe (up to 6% of annual turnover, in theory), so I see why they don't want to risk it.