I think there's an even better explanation, and liquidating $8.5 billion of Tesla stock may just be the icing on the cake:

Elon despises the SEC and he's now has exposed that the "less than 5%" of accounts are bots, that the SEC should have verified and accepted their methods for determining that number - and it should be adequate and reasonable to give a grounded-in-reality output, and it seems like it's a total bullshit statement.

I'd be surprised if Twitter stockholders don't sue the SEC.