That assumes the activists are in the right. You’ve chosen a side. Would you say “the division didn’t start with the activists” if it was conservative activists advocating for modest dress codes or similar? Your position assumes that progressive activists are correct, justified in bringing their politics to work, and that if they have a problem it’s the company’s fault.

But you have to work with people you might disagree with, including conservatives, religious people, and so on. The point of keeping activism out of business is so that people with differing politics can work together. If you can't in good conscience do that, the honorable thing to do is resign, as happened at Basecamp.