Desperation? Think they can't get anyone better?
I think some of them also think pleasant, normal men who do their own laundry and cooking are a complete myth. They weren't raised by them or with them, nor were their friends. They've never met one so they can't exist. They've only met gross manbabies who sit in dirty underwear on an Xbox in a filthy room all day. Some then post that they've had babies with them and they're still in the same underpants in the same filthy room.
It could be a class thing? All the men I know can get the baby up, dressed and in the sling and go out for a walk with absolutely no fuss. They leave work early to pick them up from school. They care for them at the weekends while the wife goes bike-riding or is on a weekend away with friends. This is all considered so normal as to be unremarkable.
But then you get women like my mum, who've never known a man could use a hoover and who still live in the 50s. Men don't cook. Men shout. Men go to the pub. Men don't look at or interact with children. She thinks my husband is 'odd' for being a caring parent. She thinks a man walking with his child down the street is "unusual."
What baffles me is how many still share my mum's views right here in threads. "Hi, I'm 22 years old and I've married a man who says I have to give up my job and stay at home cooking. Hi, I'm 25 and my husband refuses to watch the kids while I brush my teeth." It does seem so strange that younger, more educated women who have clearly seen normal men on the TV, at least, or read about them in books, end up with 1950s throwbacks.