Was he really pushed out of Facebook for being a Trump supporter?
I think he was fired because he was generating a lot of negative press/attention for what was at that time a burgeoning VR project dependent on adoption by a crowd that largely wasn't a fan of his political leanings...basically office politics.
But...he was fired with a $100 million severance [2], so it's not much of a pity situation.
1 - https://www.theatlantic.com/technology/archive/2016/09/reven...
2- https://www.fastcompany.com/90266150/zuck-pressured-facebook...
As someone who has minimized Facebook use for years and cultivated some political distance (neither party represents my views much at all), I think FB was mostly "keep your hands off except to feed people more of the things they click"