Depends what they did. Let's check the forum post…
> they had created and promoted hate sites, photoshopped images, and harassment targeting limor, me, and others at adafruit. this was done on company time, shared, promoted.
Ok yeah if a company is sharing bigoted photoshops of my likeness, yes, I'm gonna demand that they discipline the responsible employees. Obviously.
I don't have any reference point for what "hate sites, photoshopped images, and harassment [meriting HR training]" constitute, but if it's anywhere near as bad as it sounds, sure, escalate the situation and air your dirty laundry in public. This is unacceptable behaviour, and apparently it went on for years. When you're being publicly harassed, you have no duty to indefinitely restrain your response to private, polite emails.