If it was a company tweet then it would have been the board and material.
As a private shareholder anyone can say anything, but with out the board and then a shareholder vote it means nothing.
You're kidding, right?
Musk is CEO and main spokesman. Of course if he tweets - "I'm going to take this private and I've sorted the funding" it's got to be seen as a meaning what it says.
And even any private shareholder (let alone the CEO) cannot say "anything" without potentially running foul of the regulators. Stopping market manipulation is an important, and essential, activity. And this looks uncomfortably like it. Yes Musk will say - "Oh you've misunderstood, I was just saying what I thought". And it might even be true, and he might get away with it as far as the SEC are concerned. But it's one more nail in the coffin of Musk having any credibility for running a large company like Tesla, and a big one.
You can see why he is keen to take it private. He can't possibly last long as CEO if it stays public now.
You are making a mistake re the CEO who runs the company and makes executive decisions and the shareholders who own the company.
If this statement was coming from the board there would have to be an 8K, but none has been issued.
A CEO who owns less than 50% of a company can not do anything regarding the structure and ownership of the business, which Musk noted in other tweets where he said it all depends on shareholder votes.
Any market participant should be aware of this and if not they can not be considered competent to invest money.
More importantly you under-estimate the value of Musk. Had the board called the Saudi fund they would have likely refused to discuss anything with them. The Saudi's want Tesla with Musk, if he was replaced the equity would imho be worth a tiny fraction of its current valuation.
A private Tesla with Musk unleashed is a desirable thing to own which is why the Saudi's are prepared to pay billions for what ever shares they can get. If they were at all bothered by Musk they would not want to hold shares in the business.
As I have typed many times, IMHO Musk is not your average person just like Ford, Edison IMHO were not. The Saudi fund wants Musk more than they want Tesla because they see in him someone who can change the world and make them a lot of money.
Many people will disagree with this thesis which is fine. I have spent a long time studying entrepreneurs and in my view all the contemporaries of the entrepreneur didn't get why this one person was so important and made so much and at the same time why they were so unimportant and made so little. People do not like to admit to stars in business, yet do so in sport, music, film, theatre, writing etc.