I've got no 'ishoos' with people and infidelity (not just men) because for me, it's a dealbreaker if my spouse cheated on me.
That's it. Game over.
And if my spouse were out with his bit on the side and cocked up like this I sure as hell wouldn't be getting back together for him.
Others feel differently.
Each to their own, but it's oversimplifying to say everyone who feels anything other than an outpouring of sympathy for this man equivalent to that of the child's mother is a man-hating, angry person.
MN can be very man-hating at times, it can also be very Princess-Di effect.