Well, usually when buying existing properties, you are mostly buying the location. I see it more like the land is purchased and the house on it is free.
The best example is me personally. The first house I bought was before the foreclosure. After a suicide and fire. Purchase price €7,500. The value of the land was €40,000 in 2010. Of course, I renovated and have now sold it at a profit.
Second purchase this year: bought a house for €165,000. Completely renovated and overall ended up at about €240,000 including purchase price.
The land is worth about €80,000. Good location and bigger. That means: I effectively 'built' a house up to current standards for €160,000. Including finished outdoor facilities, an extra conservatory, basement, and a masonry triple garage.
Compromises in the floor plan, though. But that’s fine.
At that price, nobody builds new. Definitely not comparable.
Therefore: don’t always be so pessimistic. Existing properties can make sense.