I do agree as a general rule at least because two parents provide more financial support and generally because both parents work it's possible to always have someone taking care of the kid as long as you schedule things correctly. I don't have anything against single parenting though, I was raised from age 11 just with my mom, and yeah it was a lot thougher than before, but I survived.
Whoever fights monsters should see to it that in the process he does not become a monster. And if you gaze long enough into an abyss, the abyss will gaze back into you