Of course, it's all about the energy. I'm not a biologist, so I won't speak to the details of how resilient DNA is to specific types of exposure or why, but I am a physicist and I can tell you that if you blast DNA with high energy radiation, like gamma rays, it's gonna have a bad time. That said, if we want to talk about robustness in terms of what it's likely to be exposed to, then it's pretty darn robust. We are exposed to a wide band of EM radiation on a constant basis, and can even withstand exposures on the higher end without becoming 'corrupted'.
I'd also note that standard, non-specially designed electronics aren't very resilient to radiation either. Not to mention, if you could reliably read/write data using DNA, I'd expect that redundancy would become... easy. Security on the other hand...