Probably because the work these companies do is frequently political.
Let's be clear: What Coinbase is saying is, we the founders, who set the company's mission, and are doing so with a clear political view (rooted in libertarianism and so forth), are allowed to use the company to further our political ends.
But the staff? Sorry, you have no voice.
Maybe that's fine. The clear message to staff is: you are either onboard with our mission, or you can leave.
But let's not pretend companies and workplaces are apolitical. That's, at best, deeply naive.
Frankly, I wonder how much of what we're seeing now is due to the destruction of unionized labour, which were organizations explicitly designed to channel the political views of employees into collective action. Absent those structures, a) you get this bizarre perception that the workplace is apolitical (it's not), and b) staff no longer have a path whereby their views and values can be channeled and expressed.