There are two sides to this answer.

One side is that World War II did see (in America and elsewhere) an explosion of women a) performing jobs that had traditionally been coded masculine, such as laborers in factories making munitions and machinery, and b) joining the workforce when they likely would not have if their husbands had not been at war. From the rise of cotton mills in the early nineteenth century to the Triangle Shirtwaist fire in the early twentieth, the textile and garment industries depended on the underpaid labor of working-class women - standing at mechanical looms and spinning machines, sitting at sewing machines packed into a sweatshop, taking piecework home. The vast majority of domestic servants were female, from the basic maid-of-all-work to the average cook and parlor/chambermaid - male servants were paid a great deal more, and tended to be found in elite households that needed footmen to pass plates at fancy dinners, butlers to pour expensive champagne, and stablehands, grooms, and coachmen to deal with carriages (later, chauffeurs with cars). In the last two decades of the nineteenth century, women's participation in paying work exploded, with women coming to make up a larger portion of the workforce as they entered a wider variety of industrial jobs. In the early twentieth century, sales counters were frequently staffed with women; the new position of telephone switchboard operator was gendered feminine, and the older position of secretary became so.

(This caused, as you might guess, a tremendous amount of gender-related anxiety. Early in the century, when textile craftsmen were transitioning into factory work, they typically pushed back by excluding women from their trade unions, since female workers would be paid less and therefore threatened their wages, as well as their sense that they were doing "a man's job". Factory owners that largely employed women at the machinery would employ men as supervisors and office workers, positions that put them above the "unskilled" women and certainly gave them higher wages. Progressive middle class legislators addressing industrial workplace issues tended to take the view that the most important thing was to guarantee the working class man's ability to maintain his family - though they by no means managed to do so - rather than to protect all workers.)

During World War I and World War II, the loss of men from masculine-gendered industrial and office fields meant that there were openings that needed to be filled, openings that women weren't usually considered for if there were enough men to fill them. Most stereotypically, they picked up work in munitions factories, but they could be found everywhere - janitorial work, driving cars and ambulances, holding supervisory positions. Middle class women who had not been required to work outside the home were also entering the workforce in order to support their families when their husbands were at war, or did so in response to the frequent depiction of war work as a patriotic duty. These factors did make women's participation in the workforce during World War II (and I) somewhat revolutionary.

The other side is that the narrative of women's history is often drastically simplified in popular culture in order to provide a moral message about how and why "things got better". "Premodern times" are jumbled together in a mass of barbaric customs that saw all women treated as mindless chattel; then in the early modern period, individual proto-feminist intellectuals began to protest this treatment in writing, which progressed into real action in the nineteenth century. Women experienced freedom working during World War I, which made them happy and liberated and created the flapper. The same thing happened again during World War II, after which men tried to put women back in their place, which resulted in the second wave of feminism in the 1960s. There is a clear progression from worse to better, implying some level of natural improvement, and people and situations are filed into objectively good and bad boxes. The women on the side of progress are typically portrayed in fiction as radical pioneers, contrasted with conservative biddies and condescending old men. It's all very simple and black-and-white.

Once you begin to read about women's history, though, you see a beautiful and amazing complexity. (You can get some of this from my past answers here, but for the real good stuff you want /u/sunagainstgold's.) A great deal of complexity comes out of looking at the differences in occupations and choices of upper, middle, and working class women in their own contexts rather than assuming a unified and modern set of desires and preferences and a middle class default perspective: what did these women actually want out of life, and how did they view various activities? A working class woman might see sewing as a necessary task to keep her family out of rags, while a middle class woman could practice it as a form of craft to make chair covers, cushions, etc. for her home, and an upper class woman might produce artwork with the best materials or completely leave it off, since she could buy things that had been made/embroidered by others. Women at all levels of society could view their occupations (whether paid jobs or domestic/family duties) as careers even though we do not now see them as desirable ones. More complexity comes from simply taking a deeper dive into the sources. Widows ran their late husbands' businesses, wives worked with their husbands as equal partners. Women with social power exercised it, even against men. They wrote books and studied history, science, the arts. Here and there, it is possible to say that "women's economic power declined as guild protections were enacted" or "it became more acceptable for women to participate in that field", but the straight line of progress gets extremely fuzzy! In order for the narrative to be kept clear, women's paid employment before World War II has to be downplayed and masculine-coded occupations have to be portrayed as objectively more appealing and empowering than feminine-coded ones.