That may be the case, but you have to take survivorship bias into account, and the vast differences in available equipment and materials.
A modern double-paned house with R20 insulation and a well designed heat pump system is going to blow(er test) the doors off an immaculate mansion built in the 1900s with single pane glass and a gravity furnace.
Survivors are the only ones on the market so its already accounted for I guess. I think I misread your original comment, are you saying price for a well-built new home is similar to pre-owned good bones?
I was just noting that the prices are much closer now than they had been in the past (on a sq ft to sq ft even 10 years ago a 1970s house would be a good $50-100k less than a new house, though it was hard to compare because location, lot size, etc).
In my experience, "good bones" houses are harder to find than people realize, and there are lots of things that can wear out over time that you don't realize until you have one wear out.
For example, behold the glory of Orangeburg sewer lines, relatively common in some areas between the 40s and 70s: https://en.wikipedia.org/wiki/Orangeburg_pipe - a cool $10k+ when that finally eats it.
"The old ones are better" is sometimes true and in some cases; for example, an old plywood sided house will handle sustained water intrusion much better than a modern OSB sided house, but modern siding may prevent the water intrusion much better. There are also things that look really great but are actually disasters waiting to happen - river rock foundations, for example. A contractor friend once mentioned that the old victorians in our area were amazing except for the roof and foundation, both which can be annoyingly expensive to fix.
Based on my personal observations, assuming you avoid asbestos and aluminum wiring, the houses before the 80s are better than 80-2010s or so, especially 80-90s, as I've seen many, many cases of those houses built with newer materials that clearly the builders didn't understand or care how to correctly install.
That stuff can still happen on a modern house (hire a home inspector to inspect during build if you can) but they seem to have a better handle on how to do things right for the long-term.
A modern double-paned house with R20 insulation and a well designed heat pump system is going to blow(er test) the doors off an immaculate mansion built in the 1900s with single pane glass and a gravity furnace.