the number that have a child with a man they have barely dated let alone got to know to the point of a stable long term relationship is astounding
I agree.
but sticking the boot in when the woman cries out for help and support just seems spiteful and pointless.
Asking why is not spiteful IMO, It's a genuine question.
When I was in an abusive relationship years ago no amount of pointing out how much of a mug I was would have made me leave any quicker.
In which case, the question shouldn't have much impact on you.
I guess everyone sees things differently. If a bunch of strangers could see how crap my partner is from what I've said, then I could take it as a sign they have no vested interest either way.
If you examine the why it can hopefully prevent a reoccurrence in the future. If you avoid the answer to the question, it's really rugsweeping and doesn't help.
If you do some self exploration, it puts you in a better place. You may discover through answering questions that it stems from seeing your own mother in a similar relationship, so you've normalised it.
This then gives you insight and understanding that your own DC could normalise your relationship and repeat the pattern.
I commented on a thread recently and asked the poster if she felt lucky because she thought her partner was better looking, wealthier and more intelligent than her. I was trying to understand why she tolerated the crap. She said I was correct. Myself and others were trying to get her to see that her DD (already suffering from MH issues at 10 yo) was being affected by the relationship.
What you perceive as putting the boot in, is trying to help through getting a better understanding.
I think it's perceived as it is do, because women in that don't want to admit they have any responsibility for the situation and they feel foolish.
Sometimes, you do have to admit you messed up in order to learn and move forwards.
People mess up in all kinds of ways, nobody is perfect, but when your mess up includes the creation of a new life to a useless human being as a father, who was always useless/abusive, you realise that it impacts you and your DC for a long time to come.... and I suspect there may be feelings of guilt as part of that.