Actually I blame feminism/leftism in general, which gave everyone involved the idea that any of this shit was okay and would not result in exactly these problems.
People are animals. So society invents moral codes and customs to tame their animal behavior, prevent conflict, and channel their bad impulses into productive activity. Then short-sighted idiots come along and say "ugh, this is terrible! How dare you tell me what to do I can do whatever I want!" Enough short-sighted idiots go along with this, people stop following the rules, and then start crying when human animals act like animals. "Why are people acting like this!" Because they're people. We had rules to stop this behavior from occurring but you didn't like them, so now you get shit behavior. Start following the rules designed to prevent shit behavior and the shit behavior will stop.
You also ought to get over your puritanical moralizing about monogamy. It's not for everyone.
By what right did you call the guy a scumbag? You ought to get over your puritanical moralizing about begging subordinates for sex. It's not for everyone.
I wish this story could be broadcast to the people of the 1950s. "A company is getting ruined because female engineers are getting harassed by a pervert? Okay, first off, what the fuck are 'female engineers?' We don't have enough male engineers? Why aren't they home taking care of their kids instead of slaving at some stupid company for perverts? They wouldn't be getting harassed then now would they? Okay, okay, so now about this pervert, why doesn't he just have his own woman? Wait he does? Okay so he's cheating on her why what a piece of...hold on an 'open relationship?' She's having sex with other men...and he knows about it...so now he's hitting on everything in a skirt...THIS IS WHY WE HAVE RULES GODDAMNIT!!!" and they'd kill every feminist on sight and we wouldn't have these problems.