Now that I’m well passed the magical 40yo mark I’ve noticed my fingers aren’t as invincible as they used to be. I get random RSI strain in mu fingers and especially in my thumbs. Likely a lot from phone usage though, but I’ve noticed my keyboard habits also have a big impact. I’m not convinced that “ergonomic” keyboards that remove weird angles are a permanent solution - a permanent solution would be to not use keyboards. While I do have an ergonomic keyboard - many in fact - and they do help, it’s more helpful to rotate them just to remove the repetition. My current setup is rotation Ultimate Hacking Keyboard v2, Logitech K860 and a Topre Realforce (TKL).
What also helps is - weirdly enough - typing. More specifically typing text that you don’t normally type which in my case is prose. My current go-to is typelit.io which allows you to type classic literature. Heck I’ve read many books practicing typing with it!