Alright, it's clear that you're against this, but what's the argument for allowing this? In other words, why should the company tolerate using its channels as a soapbox to advance your political agendas, especially if it's a drain on productivity? I want to shitpost on company time/equipment/networks as much as the other guy, but let's not pretend it's some sort of right, or that being denied the ability to do that is some sort of moral tragedy.
Now a company asks its employees to forgo that power and liberty. Why did we take the power of policy from the aristocrats in the first place? We can of course go back to shut up, work the field peasant model and let them enjoy discussing policy for us while we produce goods.
What comes first? Your employer or your rights?
I don't think the French, for example, applied guillotines to solve the problem of "aristocrats talking too much policy."
There is no such monster as "politically neutral." That is synonymous with "supporting the status quo," which is a political stance. It's the trolley problem - not deciding is still opting into a bad option.
For a sample size of one, while I am very guilty of having many politically charged conversations with coworkers, I have always kept them physically /outside/ the workplace. At work we confine conversations strictly about business and customers.
During the time that the employer is purchasing from you, your duty is to your employer, fulfilling their legal requests.
If you don't fulfill this duty, they will no longer have a desire to buy your time.
It's really not any more complicated than that.
*but less often because it's harder for employees to coordinate