People seem to be discounting the fact that Elon still owns 9% of the company and is one of the largest shareholders. He just wants a chance to renegotiate as he know if he actually walks away he will lose around $5B.
So my question is: what did he learn between the point when he decided to buy all those shares at a high price and the point where he started making a stink about bots? He hasn't made any claims based on new information. Did he just spend a massive amount of money on Twitter stock with zero idea of how much it should actually be worth, and only have second thoughts after signing a deal to buy the company? There's no scenario where his actions look economically sound, so the implausible-on-the-face-of-it "do it for the lulz" argument seems like one of the last best guesses available.
[0] the internet ad space is filled with players, and generally a low-trust industry for obvious reasons, so this claim strikes me as extremely dubious, but here we are