Your model of a nuclear "stable household" is very recent, very untested compared to standard practice during most of human history and societes. Putting is on a pedestal without any quantitative evidence isn't wise.
Lots of quantitative evidence that having two committed parents means healthier kids (IQ, emotionally, physically, etc.)
Having all the responsibility fall on two mostly unsupervised, inexperienced people is fragile and "traditional" gender roles do not alleviate this.
<< "traditional" gender roles do not alleviate this.
I would personally argue that the "traditional roles" seem to help the offspring on several levels, but I didn't see many studies ( as opposed to non-traditional that is ) to that effect.
I would also argue, why does the community automatically bear the responsibility for a decision made by two?
With all due respect, Given that you’re on the path to population control and all that’s implied with that, I find it difficult in myself to take what you say seriously.