The former made it so that women no longer had to go to the market once per day. Instead, they could do one week's worth of shopping and store everything in the fridge.
The washing machine made it so that they no longer had to spend hours everyday washing clothes.
With all this free time, they could now start working outside the home. So they joined the workforce.
Bottom line: Do not be so quick to dismiss an idea. Things are often more complicated than they seem on the surface and can make a much bigger impact than you think.