If I was running a company, I would prefer employees not to talk about politics because it will create needless arguments that have nothing to do with the job at hand. If I am an employee, if there is a disagreement about something, how do I know there is not going to be a long-standing hatred from a colleague about my position on a topic that will manifest itself in unpredictable ways.
There are too many activists which make every topic good vs evil and life vs death.