Re: Chilling effect ?
That's a good point, but while the SEC might go after Musk for being a basic dinkwahd, shareholders only have limited recourse against the existing board. And of course only if they don't get their $54.20 a share... if they do, or are "made whole" by (hypothetically speaking) Musk paying Twitter enough cash to increase the value of the company to the point where each share is worth $54.20, they won't have a leg to stand on.
The consensus amongst those who know seems to be that this is going to cost Musk ten figures, but opinion varies as to whether it's low (the $1b breakup fee), middle or high...