A couple hundred mostly-males built a company that was wildly successful where they loved to work. Now it sounds like they have to destroy that, build a culture that is professional and antiseptic, to make feminists feel welcome.
It doesn't have to be "antiseptic" at all - there are plenty of thriving, wildly-successful, mostly-males companies with great cultures where women feel comfortable too.
Also, it wouldn't be changing it "for feminists" - it's changing it to welcome any people, of either sex, who aren't comfortable in that environment. Just because feminists might be the most vocal about it doesn't mean it doesn't affect others too.
They don't even have to change their culture at all; all they need to do is to tone down the more aggressive parts of that culture towards certain people. Which shouldn't be difficult - I'm sure all of them have friends with whom they're more calm and less aggressive, or family members. They just need to transfer a bit of this thoughtfulness to the office.
It's not about changing because feminism, it's just the human decency of being reasonable and respectable to everyone, as far as is possible.
