I've figured it out. 

Elon was always about screwing with the market. That's why he got tesla to buy bitcoin and support it.
Why?

Well, how do you get the 'World' to trust you.? In order to pull off dumping a market you never had anything to do with?
Easy, you do them a solid. Do them a favour. Then your very highly thought of. 'good ol Elon' - 'Elon leads the way.'
By buying Bitcoin at an overpriced/overbought stage in the market he gave the current over-extended price structure; validity. He authenticated it to some degree.

Then; being the 'spokesman' for bitcoin adoption by institutions + billionaires - that he managed to appoint himself with the crowd by said deed, he now had a lot of power  over sentiment ^^
Then, shittalk the asset you have become affiliated with by your 'good deed'. It dumps.

I suspect Elon believes in Bitcoin. And wants to help dump it to fill his bags. He's doing a good job so far.



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It was a clever piece of market manipulation. He's a scumbag.