Even reading is a destructive process, and the physics involved are incomprehensibly complex by comparison with anything in the digital domain.

There are ways to read it nondestructively. One way does trade resolution but once prepped the DNA itself can be imaged to be read.

https://en.wikipedia.org/wiki/G_banding

That does not read DNA. A chromosome is not a strand and a karyotype is not a sequence. In any case, I described what a ribosome does.

Sorry, it is one of the most stable organic molecules and can stay intact for thousands of years. That is why the Jurassic Park like fantasies are based on a truth and many extinct species have been brought to life through DNA in reality too.

I think maybe they are talking about the very tightly packed yet still functionally accessible 3d structure that is chromatin, not individual strands.

No, they haven’t. Any claims otherwise are as real as “T Rex Leather” handbags.

How do forensics for old cases work? Is it because of probability. You don't need all the data but if enough of it matches it convinces the scientist of the match?