We also had slavery, no advanced medicine, no education for most people, and an average lifespan of about 30. Amazing how selective nostalgia can be.
Letting the other 50% of the population make the same life choices is a good idea in my opinion.
Letting someone make free life choices is good. Disincentivizing not working isn't. It's a reasonable choice for one adult in a family to not work, especially if their earnings don't exceed the costs incurred by having both adults at work. We shouldn't set up our societies in a way to forces people to work even if it makes no financial sense.
We can all go nomad and berry-picking anytime, then.
The people who wrote the policy presumably want both parents to be able to work. It's the main reason to make childcare free.