And I would like to emphasize your point and add that the dismissive observation really isn't helpful because the main point is especially true for those who really do struggle.
If the highest-earners of the middle-class have their discretionary income locked up in housing costs, how much more difficult is it for those who don't have the same level of income. Housing then eats into non-discretionary expenses.
Dual income families are — and for decades have been — spending their extra second income on housing rather than the rest of the economy. The comment you’re referring to is therefore very relevant because it shows that trend in action. Housing — and other opportunities in life it enables, like access to schools, (real life) social networks, safety, etc. — supersedes everything else in importance for many families, so second incomes are just spent on what is ultimately a bidding war over housing.