It's not about hoovering and housework.
Many jobs require you to be at work and prioritise working hours. In many jobs, travel is expected, over-time is not even "overtime", it's just flexibility around work commitment (which work both ways)
You cannot and will not be considered for the position if you miss breakfast meetings because you had to do the nursery drop off, if you refuse to be around later in the day because you have to pick-up from the child-minder. It will not be a positive that you stay at home randomly because your kids are too sick to go to their nursery or child-minder, or just stay home when they are old enough for school.
You can't be at work and taking your kids to clubs, to parties. There's only so many favours you can ask from friends.
You can't have days off everytime the school is closed, for holidays, for election days, because there's a burst pipe
Some jobs you can juggle more or less easily, a teacher cannot just drop everything and run to their own kids leaving the class alone and someone to take over. My friend who works security in a London airport couldn't manage without her husband working from home and her mother living next door, her shifts can start way too early to leave young kids alone.
It's very easy to pretend you can have kids and work as normal, but it's simply not true. Or not in every field. Some jobs are fine and flexible, no evening, no weekend, no travel.
There wouldn't be any SAH dads if it was always so easy to juggle everything.