You can't stop entropy. Archeological sites that are not dug up and actively preserved are destined to be lost forever....always
I don't disagree, but that's true for literally everything in the universe. And digging it up, speeds up the process. Yes, some items you could enclose in carbonite but unless you do that to the entire site, much is going to wither significantly faster. The same how using an artifact would also speed up the process.