Absolute rot!
I was a SAHM until DS was 12 years old. We moved when I had DS, the job I did involved late night meetings and DH earned enough for me to take a few years off. Those 'few years' turned to 12 years during which time my mum developed Alzheimer's and I started a small business (yes, to fit around DS and DM).
DH, because he knew how much I valued my own time, would regularly book me a weekend away in a hotel giving me time to see something at a West End theatre or do some trade shows for my business. That happened from DS being 6 months old. During those weekends DH was on his own. He, like me, figured out what to do with a child who was sick or teething or was having a tantrum. Because, like me, he's an intelligent human being. I didn't get an instruction manual, neither did he.
He also took DS away for a week to visit relations on the other side of the country on more than one occasion. Giving me the chance to do stuff around the house that I'd been putting on hold and to get out to see friends without the 'got to keep a clear head because of baby'.
I've rarely done ironing in this house for three years. DH took it over when he was made redundant, then mum became ill and I was to and fro hospitals. He's never handed it back as he finds it therapeutic apparently (very odd - I hate the job). I'm in charge of cooking as he hates that job. But I'll iron and he'll cook if need be - stuff doesn't sit around un-ironed and no-one starves if the other person isn't there!
He is more than capable of cleaning the house (and does) just as I'm more than capable of fixing stuff and do (because my dad taught me how to do DIY).
The point is we're a team. If something needs washing the person nearest will wash it. If DS's nappy needed changing when he was a baby, the person nearest would change it.
So DS has seen that sometimes jobs in the home are done by one person who either enjoys it, is good at it or hates it the least. Sometimes the jobs are shared on a 'whoever gets there first' basis. He finds it weird when friends say 'dad doesn't know how to use the washing machine or doesn't mop the kitchen floor. He also finds it equally weird that friends mums can't put up a shelf though. If you asked him what was a SAHM/D's job and what was the working person's job I don't think he'd understand what you mean - it's a house with people in it that need looking after so it's everyone's job to chip in.
So SAHP aren't to blame here. It's people not prepared to pull their weight regardless of working status or gender.