It doesn't even say whether they went to an actual doctor, just something about acupuncture physiotherapy and various medical ideas they might have just googled on their own.
Seems like a bizarre omission from the article given the number of tangents and topics covered. My guess is that going down the traditional medicine route lead to him being told there was no organic basis to the pain.
As someone who went through a similar experience, I would not be surprised if the author's pain is/was entirely psychosomatic (this doesn't diminish its severity or significance). Probably a direct result of burnout.
The question here isn't about damage but about what mechanisms in the "pain pathway" are responsible for OP's specific experience of this pain. One day he has sudden, debilitating pain - in both wrists - in the absence of a traumatic event. He's conspicuously omitted any kind of medical diagnosis, and the whole thing is part of an existential crisis on the tail end of an insane, psychologically unsustainable workload. Not a typical presentation of RSI, that's for sure.
author here: i definitly agree its a bit of both. but i will say, taking 2 years off work, still hurts if i build furniture or have to hammer something or turn a lot of screws