3 possibilities:

1) Elon is trying to position himself as being "pro free speech" in the same way Jack Dorsey did (it's just marketing, and not a truly held principle).

2) Somebody in the organization is making decisions that Elon will reverse in the next 24 hours to prove that they did not come from him.

3) Some specific threat has been made against Elon that has him now paranoid about his security to the extent that he's rethinking his principles when faced with his own mortality.

The difference between 1 and 3 being whether he never had principles or is now giving them up. I'm guessing it's 3 because I've seen SO MANY public figures I once respected do the exact same thing once the danger of standing on principle became all too palpable.