If someone smokes for 20 years and doesn't have cancer yet, was it a good idea?
Sure, a lot of things must add up to create RSI. Stress, no breaks, no stretching, age, bad desk/chair/monitor placement, the genetic lottery, the QWERTY layout, mice and reliance on GUIs, and heavy keys, multiplied by years of use will just about do it. Young programmers: you are not immune. Fix those risk factors.
I used Model Ms for years. The high force switches were painful. It took too long to recognize this because I loved the Model M. It looks great, it's well made, it sounds badass, and it kills hands.
The Kinesis does everything well. It makes you a more efficient typist, by forcing you to touch-type and putting return and backspace at your thumbs. Your hands never need to find their place on the Kinesis, they only fit in one place. It's TKL, NKRO, firmware-programmable with macros and stuff. It's a great design that just happens to be ergo.