@DaintyDinosaur
Over time, I have started to think of it more as a social issue however. The world sanctions women staying at home with their babies without question. We are still far from being equal parents And most employers are still surprised by men wanting to work part time or do the school run after they have children. I do think there is a large social component to the gender pay gap which requires a big cultural shift. It should not be assumed that women want to stay home with their babies and give up work.
This is exactly the point and this is fundamentally what "mental load" is about. It's not about people being bored of doing their washing and life admin or whatever. It's the fact that society still hugely disincentivises men from pulling their weight at home and with children.
Our society has (largely) made peace with women going out to work: that battle has been fought and won. What its barely scratched the surface of is the ongoing fight to get men to step up domestically and in childcare and life management.
As plenty of people have pointed out many women genuinely do want to remain at home with their children or work PT and there's nothing wrong with that at an individual level.
But at a societal level this trend underpins a vicious circle whereby the entire modern economy depends on the non-working or low working woman to do all the tasks -- let's call them "mental load" which the high earning partner can't or claims not to be able to do. You see this endlessly on threads: "I gave up work and that enabled him to do much better in his career." This statement always annoys me because it more or less acknowledges that the DH in question with his Big Job can't do anything at home.
This makes life much much harder for women like me who have to work to survive, and indeed for many women who don't have to work but choose to work. Because the whole default setting of the modern economy continues to be based on an unspoken but unshaken assumption that there is always someone (and by someone I almost always mean a woman) who can pick the kids up from school, take them to the dentist, sort out the food deliveries, pay the bills, book the appointments, book the holidays, be at home for the Amazon delivery, communicate with school, go to parents' evening. The whole endless, relentless trail of stuff which has to get done, regardless of what your employer wants.
And as women tend to do this by default, it's much easier for this whole infrastructure not to undergo the disruption it needs: for employers to look down their nose at men who want to go part time or who want to cry off the golf match because their kids are sick. Or for employers to be sniffy and refuse to promote women who choose to remote into a meeting because their childcare commute doesn't allow them to get into the office. It goes on and on and on and I've been on the raw end of the disadvantage that natural male inertia creates in my work for the best part of a decade.
So when people say; "but loads of women just don't want to work": I think: yes it's true. And of course no one should have to work if they don't want to and can afford not to. But in a large number of these cases where women supposedly don't want to work women actually don't work because they can't make having a job work on top of the slew of stuff they know their husband or partner won't help them with.
And I come back to the fact that what really needs to change is for society to much more deliberately tackle this infrastructure of male inertia about supporting women at home.