I disagree that construction quality is lower now. The building codes have become ever tougher over the past 50 years. I’ve lived in a 60s house and a 70s house in San Diego. The 70s house is clearly more earthquake-resistant, has safer wiring, and more. When we remodeled, the current building codes required insulation, double-glazed windows, and other features that were missing in the 70s.
The same is true in other parts of the US also. A Florida house built now is considerably more hurricane-resistant than a 10 year old one.
And the same is true if you compare a new condo downtown to one that was converted from a bulding built to decades-old standards.