It’s not such a bad idea, and it was the initial intent of blue checks: proving that an account wasn’t impersonated. But they couldn’t roll out verification at scale, so they only verified high-ish profile accounts. As a result, over time, the blue check has come to be a sort of class signifier and lost its original purpose (I sometimes see verified anon accounts, what even was verified?)

Rolling it out at scale could improve the rampant spam/astroturfing problem, even if it would be imperfect.