My guess is that the population on your message board changed over the years you were on it. Women no longer need a "safe space" on line. Rather, a certain politically active group of women need an echo chamber in which to remind each other that it's ok to complain loudly about nothing.

Your group suffered the fate of our political parties, taken over by extremists thanks to the parties' success at gerrymandering. Swing districts and swing states are essential to effective government by compromise and moderation. The safer a voting area is for one party, the more extreme the candidates who can win the primary. The non-zealot's best argument is "S/he can't win the general election." Take that argument away, and only the crazies get elected.

An all-female message board is effectively a gerrymandered jurisdiction. Eventually, the wackos take over. As they have.