If you create your data right, the actual data can make backups of itself. There's even builtin ways for it to improve itself over time using genetic algorithms.

A kind of implied meaning of the term "data", especially in context of storage and archiving, is that we do not want it to "improve itself".

DNA/RNA looks to be more like storing heuristics, landmarks and clues, not data.

Can you elaborate on that? A significant portion of DNA in organisms literally encodes for protein sequences. It also has functional parts (binding sites for proteins, promoter sequences). Some RNAs are not translated because the RNA itself has function, but I don't see that same argument for DNA.

And like 90% of E. coli genome is protein coding. I intentionally wasn't limiting it to humans because humans make up a very small portion of total DNA in the world.

Having an error rate means a small chance of gaining an edge that makes up for having it.

Could make for some interesting decoding errors as your original data mutates