It would be simply out of survival instinct. Sufficiently strong leftist political views seem to correlate very strongly with the desire for people to mandate others fall in line with their views. Or else.... how many examples do moderate/conservative people need to see before they should worry? Or simply.. go elsewhere.

Openness, or simply indifference to personal or political beliefs I thought was the DEFAULT position of most people.

It is sadly not that way anymore... this and many many other examples have shown us all.

Just search twitter for hundreds of tech-industry employees railing against this guy for trying to present a statistical argument against conventional wisdom. They are no doubt celebrating at this moment that he was fired.

Anyone on the fence just needs to ask themselves... what would happen if these same people knew what was in your head? If they heard you speak about your own views? Would they have mercy? Of course not. Who's next?