I tried all manner of keyboards over the years, and in my opinion, none of them solve RSI. I'm now back to a standard qwerty for the same reason as OP - they're just immediately available everywhere.
What did help my no-longer-existent RSI was simple - I don't rest my wrists any more like I was taught in high school typing class (by an instructor that would whack our hands with a ruler if we were caught resting our wrists).
I do have a bit of De Quervain's Tenosynovitis from the mouse, but I'm solving that with one of those hand stretchers that hook to your fingers and provide resistance when opening the hand. 100 reps a day (25x4) and I haven't really felt it in weeks. Turns out that working out the muscles opposite to the ones you think is the key (therapy putty did nothing).
I've tried a lot of keyboards over the years – ergonomic ones, such KA2 and Glove80 (now) absolutely did solve my RSI issues. Pain may have many issues, such joints, posture problems (pinching nerves in shoulders/elbow) but getting a proper chair and ergonomic split keyboard is still my number 1 advice. Also more sport, if it is not too severe.
Going to a doctor should also be high on the list, but unfortunately, I have yet to see one willing to do a proper diagnosis. My experience there is more than mixed, so you have to experiment yourself.
I too have had positive experience switching layouts for RSI (cubital tunnel specifically). While I am a bit skeptical on some of the more subtle claims by ergonomic enthusiasts, simply being more intentful around wrist posture seems to do me wonders. It may be more of a case where engaging in the niche is serving some broader truth, but I too directly associate my related journey to funny looking keyboards!
FWIW, all a doctor did for me was affirm my self-diagnosis and life-style adjustments. Surgery in this area looked quite grim on my last purview so I am not sure a doctor would serve much for most in this regard.
Personally I started getting wrist pain 2 or 3 years ago. I have been using Colemak anyway for more than 15 years - my original reason for switching was because the German QWERTZ layout I grew up with is not very programming friendly, symbols like []<>{}/\ are hidden away behind hard to type chords. I found as a nice side benefit that my typing speed increased by 20-30 or so WPM... I did also have typing classes in school, so it is not simply because I started paying more attention to learning how to type with the new system.
After switching to a split keyboard my pain went away, and I think I learned that at least for me it was caused by exactly these symbols - on both US QWERTY and Colemak when you constantly type [];:{}| and so on, your pinky has to reach over to do it. At least for me that meant contorting my hand a bit to reach over. On my split keyboard all the symbols are behind a layer on the home row, and I barely use the pinky for anything, which fixes the issue. I also learned to hover while switching to the split keyboard, but that did nothing for my wrist pain when going back to my laptop's built in keyboard - after a full day of programming there the pain is back.
> on both US QWERTY and Colemak when you constantly type [];:{}| and so on, your pinky has to reach over to do it. At least for me that meant contorting my hand a bit to reach over. On my split keyboard all the symbols are behind a layer on the home row, and I barely use the pinky for anything, which fixes the issue.
On a completely standard rectangular-block keyboard, I don't use pinkies to type. Actually, I do use my left pinky to hit left shift. But that's it.
There is a subset of split keyboard layouts which solve for this by moving the modifiers to the thumb area, which is often void when a keyboard is split. Quite a pleasure to use and has much less buy-in than QWERTY alternatives.
Maybe my hands are small, but to type []|\+= and not use my pinky I would either have to move my entire hand over or contort it even more to use my ring finger
I find that just going from a membrane keyboard to a physical key switch keyboard with bump that it helps a lot... I type relatively lightly. I really like the original buckling spring keyboards from Unicomp, but others around me prefer me using my Cherry MX Brown switch keyboards which are relatively close.
The physical bump helps you type without bottoming out with practice it helps a lot with RSI, at least from my N:1 experience.
I tried all manner of keyboards over the years, and in my opinion, none of them solve RSI. I'm now back to a standard qwerty for the same reason as OP - they're just immediately available everywhere.
What did help my no-longer-existent RSI was simple - I don't rest my wrists any more like I was taught in high school typing class (by an instructor that would whack our hands with a ruler if we were caught resting our wrists).
I do have a bit of De Quervain's Tenosynovitis from the mouse, but I'm solving that with one of those hand stretchers that hook to your fingers and provide resistance when opening the hand. 100 reps a day (25x4) and I haven't really felt it in weeks. Turns out that working out the muscles opposite to the ones you think is the key (therapy putty did nothing).