Totally the opposite. Doing even just 3 hours of constant physical labor over a few weeks and my joints are aching, lost mobility in my right foot. Looking after kids is qualitatively easier.

Another part is that most modern parents are subject to predatory lending on a scale that would previously be unfathomable.

Even the ones who manage to understand and avoid the predatory lending are still subject to competing with everyone else's speculated future earnings. Mortgages in their modern form should absolutely be made illegal as they bid up land prices to the detriment of almost everybody.