does the SEC have a case? Elon can say the post was a joke (probably the truth), or that he sincerely intended to take the company private at $420 after smoking

does the SEC have a case? Elon can say the post was a joke (probably the truth), or that he sincerely intended to take the company private at $420 after smoking a joint with a potential backer but then later thought better of it, say he even confessed that his tweet was a deliberate attempt to mislead short-sited investors in a lapse of moral judgement; it would still be just a note on a social network, not an official company announcement. what if he left his phone unattended and someone made that tweet, would the SEC be suing him for negligently managing his twitter stream? isn't the real problem that too many "investors" are making short-sited decisions based on nonsense posted to social networks?