I think this is it. Surely advertisers are smart enough to see this though🤷

Haven't most big advertisers left Twitter because the site has literally negative moderation? The description I've seen ppl give for current ads (i don't see em 🏴‍☠️) boils down to porn, AI slop/scams, random pyramid schemes, far-right political bs and random promoted tweets that aren't really ads

They probably do. But they are merely middle men who in turn show the big numbers to the brands as proof. And the brands use the big numbers with their executives.