This is true, but the board allegedly pressured him into resigning the week after. Here's the NYT article with details - https://www.nytimes.com/2017/06/21/technology/uber-ceo-travi... - although, given the lawsuit, it's not clear if the reporting was completely correct.

People will downvote a comment that is objectively incorrect. I wouldn't take it personally.

Enacting a coup while the king is absent from the castle is a common tactic.

You made a claim you didn't have the facts right on.

If someone without the relevant information reads it your comment could thus spread misinformation.

And so people downvote. The other replies that got downvoted after that I don't know about though.