> It has a lot more to do with protecting their buildings from angry invaders
Well, time changes. We no longer face the threats of the barbarian hordes of northern Europe but we have modern day speculators that will torn down anything for a profit and not think long term.
And again with the culturally valuable. What is valuable today might not be years from now or viceversa, that's why deciding what should be protected usually requires quite a lengthy process.
> Can you imagine not having Independence Hall today because historic preservation statutes decided to preserve all the historic Chestnut Street homes that were torn down for it?
Or having it two blocks up from the current location? But listen, I'm not arguing that everything should be preserved for ever. And I don't know any preservation society that thinks in those terms. What I'm saying is that deciding what gets preserved and what does not is a tough call and a very complex issue.
You asked where's the evidence that historic preservation, as a whole, matters. I'd argue its pretty evident. Yes you are right when you point out that the system can be abused but that doesn't diminish the importance of building preservation initiatives, specially in country that has a short history.
Also, no such thing as survivor bias when applied to hypotheticals, for obvious reasons.