Abuse? Ad tech doesn’t give a shit. Ad tech is complicit. And it isn’t just dictatorships - it’s the powerful in general (eg how they censor pro-Palestinian content [1]).
What do you do in a situation like this? Simple. Let Facebook open source it’s policies and algorithms which regulate its platforms. Let us see what the watchers have deemed worthy of censorship and intervention. Let Facebook publish how much the Egyptian and Saudi governments spend on their platforms to undermine their citizens. They won’t though because Facebook, in this area (foreign power related) has carefully ensured that it remains aligned with US foreign policy positions.
Modern day ad tech is all about tracking and targeting groups based on their interests, something any government trying to deal with dissidents will be interested in.
There's also that pesky detail where dictatorships abuse adtech to subvert democracies, stir unrest, and force authoritarian trojan horses.