Married couples with $300k combined incomes can easily buy houses. Maybe not in the Bay Area or downtown Manhattan. But easily doable elsewhere with equally good paying jobs: Austin-Texas, Raleigh-North Carolina, Seattle suburbs, etc etc....
Now try having a married couple buy a house in any major city in China without both parents helping.
Competition is less in America than in Asia. Pay is higher too, life is easier. And until recently, opportunities were also better. That has always been America’s advantage.