Well first off, I wouldn't say I took it personally enough to be "offended." That would entail a level of giving a shit that I just don't possess
Something being a product of the environment does not prevent it from becoming physiologically wired. For example, people who grow up in Japan develop differently shaped ear cochlea than people in England. Take a baby out of Japan when she's born and plop her down in England with English parents, and she'll develop cochlea suited to hear English sounds that aren't present in the Japanese language. Environmental stimulation, physiological response.
The problem with nature-nurture debates is that they assume a dichotomy, that things are either one or the other. This, of course, is bullshit. Nurture is the process by which natural potential comes to fruition. Within our genes, we hold the building blocks to become many kinds of person. But most of these blocks are cemented in early childhood and cannot be changed in adulthood. Sometimes they're cemented with flour paste and only minimal effort is required to build something different. Sometimes they're cemented with industrial strength mortar and re-wiring is a lifelong process.
Hard-wired is not synonymous with permanent. Any computer can be rewired. The process is simply more involved than software upgrades.