Inaction against intolerance is a form of action, is it not? "Bee kind" is not just a call to not be mean, it's a call to act in kindness.

I believe the poster is probably right in that it stirs more toward fostering acceptance rather than simply ignoring hate.

It's not compelled speech, per se—Beehaw users need to have an active role in order to make it the kind of place people want to bee.