> it's still worth something to the people who still pay for it.
Sorry, you're being deliberately obtuse here. If what the lawsuit claims is true (irrespective of whether it's legal or not), ads on Twitter are still worth something also to those who DO NOT pay for them, because otherwise they would not need to collude with their competitors to make sure they're also boycotting.
I'm not saying that this can be proved to be an anti-competitive behaviour. Just that it destroys the narrative of "ads on Twitter are a negative value for the brands that advertise there".