Most of the tech billionaires are conservatives (Musk, Thiel, Graham, Ellison, etc.)...are you suggesting that they are for some reason conspiring to silence themselves?
The billionaire executives are much more conservative than middle managers, HR, corporate drones. But even at the top level you have plenty of liberals (Omidyar, Bezos, Zuckerberg, Pichai…)
you probably have to differentiate social liberals and fiscal liberals.
What makes any of these rich corporate assholes "liberal"?