Whether that is true depends on what kind of place you want to buy and the amount of the loan. In Boston's north shore, the only available apartments are triple-deckers where you can hear your neighbors, for $2500/month, while houses are something like $800k; I consider renting to be a poor value here. In Cambridge, MA rent is higher, an average of $3500/month and you can choose between a commercial apartment and triple-deckers. An actual house is something like $2 million, although if you are okay buying an apartment or the top floors of a triple-decker, maybe you could get one for $1 million. I'm not interested in buying somewhere where I can hear my neighbors talking, so triple-deckers are out. Here rent is a little better deal (except that living in Cambridge is a bad deal). In the far Chicago suburbs (admittedly not "most metros"), on the other hand, rent for a decent apartment is close to the price of a monthly mortgage payment. And if you can pay most of the purchase price (or the price is cheaper), buying looks better, because you have less interest.

This is more complex than "houses cost less then".

Given a fiat currency and fractional reserve banking, the dollar floats in value like a leaf on the wind.

Houses cost less, people made proportionally less (inflation is a consideration here), and interest rates still bite you in the butt over the long haul, regardless of your monetary baseline.