Because saying that he was taking the company private affected the stock price.
Officers of public companies have to be careful about what they say.
“Because saying that he was taking the company private affected the stock price”
More so for $420 a share. It was a vindictive move to financially destroy the large hedge funds shorting the stock as the TESLA financials were not adding up. I believe these hedge funds will be coming after Elon / Tesla in civil court for a lot more than the peanuts that the Feds are.
I think the worst problem was the claim of “funding secured” for going private. Claiming such a thing when in his position must be verifiable and in writing when you announce as it can (and did, in this case) affect the stock price.
Often, days are spent in advance before such announcements. This is to make sure all legal requirements are covered. Then the announcement is usually read a press conference to ensure no mistaken words are said.