Well, it’s possible that that was a component, but (see Married Women’s Property Act ) can’t have been the full story - women who worked didn’t have control over their money until the very late nineteenth century anyway.
I suspect there were a number of things going on - practical things, and status things.
Until, say, the fifties and the advent of labour saving devices, there really was at least a whole grown-up’s-worth of work involved in running the average size household - cooking, cleaning, washing, childrearing, it was all really labour-intensive. So if your household finance was in such a state that you needed to have every “work-ready” body (meaning everyone over about 8) leave these tasks to go do paid work, it meant that you were in a bad way. You’d be wearing badly-washed clothes and eating porridge or plain boiled veggies for your supper. It really only made sense if your household was desperate. If you didn’t need the income from everybody, it made the most sense that the mother of the house should be the one at home, doing all the dozens of jobs that really really needed doing (under some circumstances a mid-size or older daughter would do, but by the time a daughter grew to mid-size, the pattern would probably be set). Part of that was, of course, that it was enshrined in law that women could be paid less than men.
Then, there’s status issues. In the industrial revolution there were a whole lot of women working (mostly young girls) but it was nearly all low-paid low-status work in very hard conditions. Certainly not a career, not something that would give you freedom (and those working girls would be expected to give up all or most of their money to their mothers for the running of the household, there wasn’t the sense of the freedom of earning your own money and being in control of your own life that we have today). When they married, they would be generally expected to stop working, and I bet the general thought was thank God for that. I know that’s what my Nan thought when she gave up nursing to get married, and nursing in the '30s was practically lap of luxury territory compared to being a mill girl in the 1850’s
Going further up the ladder, women had never been let into the higher status skilled occupations - crafts and trades or, even further up, the military, government or business. In earlier eras, again there was a fairly practical reason for that - if you were the daughter of a medium status man (craftsman or businessman, say) then you’d similarly marry someone of similar status, have a budget for the servants which would be required to keep a mid-status or higher household in operation and - bingo - there’s your job for you. Someone’s got to supervise the servants rather than earn the money and again, in all but exceptional circumstances, it’s a lot easier for the man of the family to do it. Some women would never marry, but they would generally live in a household that included married family members - their parents or siblings. Not to do so would have been highly irregular, socially, and cause a lot of unfavourable comment on their morals.
By WWII, a lot of those social pressures were starting to change. There had already been some opening of mid-status jobs for women (teachers and nurses) so there was no longer quite the automatic feeling that if you were a woman working it was probably because you were in a desperate situation. The status was starting to improve. Household work was becoming less labour-intensive, freeing up women’s time a little, and sexual mores were relaxing meaning more possibility of single young women setting up on their own, or with other single young women. Even then, a vestige of the whole “high-status women don’t work” attitude well into the 50’s (and, don’t forget, really high status men didn’t work either. These days we despise people who have no job and no qualifications - not so in earlier days where the ultimate status lay in having an independent income and not having to work - for men as well as women)