I'm not sure whether he's just abjectly stupid or deliberately sabotaging the platform to drive certain people away. It's clear that facts don't matter to him and he will not back down on being wrong. He was wrong about bots before the purchase and is still wrong; I'd imagine multiple engineers have shown him the data over the last week. He doesn't understand the point of the blue check system, which was to entice celebs (by preventing them from being drowned in thousands of replies/notifications to their posts) and provide verified accounts the ability to tweet out news/information (politicians, news and sports journalists, etc).
So the result will be a flood of troll/spam blue checks posting fake news. Fake Woj accounts announcing fake NBA trades, fake Fox News accounts announcing the death of world leaders, etc. Elon has said that scam/fake accounts will lose their blue check but we've all been on the internet long enough to know that's not going to stop what's coming. Perhaps more importantly none of this adds up to a big enough financial incentive for this to make sense. I'm sure some true believers will purchase a blue check. Most people won't.