Along the same lines, I'd be surprised if Roddenberry's promiscuity wasn't typical of Hollywood producers from the era in general. Lots of powerful men over the generations have seen themselves as entitled to sleep around and seduce women.
Its terrible to think that if women wanted to get roles in Hollywood they'd have to sleep around because there were men in power who made decisions on who to cast. And not just in Hollywood. My mother tells stories of girls who slept with the creepy old bosses (in retail) in the 60s to get ahead.
Thank goodness for sexual harrasment laws to give women a chance nowadays.