If such a discussion is not expected on HN, I am probably in the wrong place.
> cause for Brexit.
> Such extreme groups should never be allowed.
I surmise "extreme" in this context merely means "conservative" or "isolationist".
Voting for Brexit is hardly extreme or fringe. So much so, in fact, that most of the UK did so.
It's not a coincidence that Google ditched 'don't be evil', and doing that doesn't indicate a twist to the far right or anything of the sort: It's just the reality that being a wildly profitable advertising firm can require a lot of moral/ethical flexibility that leads to outcomes like what we have here with CA & SCL.
The significance of CA's politics is specifically that they gave their services for free to a political campaign that aligned with their goals, which is already of questionable legality - and in this case, likely expected and possibly already received regulatory kickbacks in exchange. But that doesn't really matter in the context of FB deciding to enforce rules.
EDIT: To clarify, Trump's campaign did pay CA but sources have claimed that they received a deep discount.
A completely hands-off approach is also corrosive and destructive. They're stuck trying to thread the needle, to balance civic responsibility while avoiding being an overbearing gatekeeper. I don't think it's possible to pull it off in such a way that they are not overstepping bounds in one direction or another, but as long as the pros outweigh the cons of whatever approach they take, it'd still be infinitely better than doing nothing.