I don't have proof that less finger distance means less hand work means less pain, so maybe you're right, maybe it's just a coincidence.
Or maybe less finger distance means less work which means less tension accumulated in the muscles and then indeed less pain.
Nonetheless, I changed "fixed my RSI" by "fixed my RSI problems" thanks to your feedback, which should clear out the misunderstanding.
I'm a long time Vim user, myself (and no, not looking to spark a holy war here). One observation I have about my own habits is that I subconsciously slap the ESC key every time I'm done with something, even if I'm in a non-modal editor like Notepad or SQL Management studio. It's just become so ingrained in me that I can't stop doing it. Mostly because there's no negative feedback loop associated with doing it.
That's not a good metric. In your case, you might be right, but for the general public it's like when picking up any new exercise or sport, like running or biking or anything really, when untrained you end up for the first few days with sore ligaments, joints and muscles. You get used to it.
My hands never hurt, even though I love writing long texts, long emails, long code comments, etc. I can also do 120 wpm but I don't feel the need to do it because it's stressful, not necessarily on the hands, but on my thought process. Speed isn't an issue.
If Dvorak solved your RSI, that's awesome, I can understand why you switched, however I don't think this is a causality issue, meaning that I don't think it was Qwerty that caused RSI in the first place. If Dvorak is a good strategy for you to manage the pain, then great, but it's pain management, not a cure.
I also used to configure my machines a lot, going into a yak shaving rabbit hole every time it wasn't functioning properly. I was on Linux back then, but I gave it up and nowadays I'm much happier. The only yak shaving sink I still have is Emacs and I'll get rid of it as soon as I find something better.