Earlier quoted context omitted.
Agreed. If raising a child were to cost $1M in 20 years, that would average $50k/year. I earn about as much and have two kids, so I imagine I would have noticed if it was that expensive.
Factoring in 5-7% annual return on investment, it's only about 25-30k per year, not 50k. (Given P(0) = 0 and P(n) = P(n-1) * 1.07 + $25,000, P(20) would be $1,024,887.31.) Perhaps still a bit high, but not too far off, especially considering that the second child probably has a lower marginal cost than the first.
I could argue that $25k/year is still very high compared to my experience, but I have no idea how much daycare, healthcare and education cost in the US. It probably makes no sense to compare costs to a country where I would earn over double my current income...