> the problem is the lack of differentiation between bots and real accounts

Nah, I'd bet that it really is as simple as the fact that the first thing Elon sees under any and everything he tweets is a flood of cryptobot fake posts and scams. That he and we identify them quite easily, and he's just flat-out tired of it.

If clamping down on API access also curtails a significant proportion of those posts, then he'll do it, even if it's just a temporary relief.