deskthority

I Touch type colemak on a matias ergo pro, but catch myself using ring finger instead of pinky often. Are there any consequences? ring finger is longer and requires less of a wrist twist to reach keys, particularly on the right hand. Who came up with the finger rules? Are these from the typewriter times, where there were little to no backspace and symbols?

I was typing on a maltron before, which has a matrix layout. Maybe that matters.

Relative ring-finger length varies (it's associated with testosterone levels).

It kinda makes sense to use ring fingers for stuff like number-row 1/0 or adjacent punctuation on upper rows. Or the outer "control" keys. There's nothing wrong with that, as long as you don't bend your wrists awkwardly to reach those keys. You probably aren't even imposing a significant amount of same-finger keystroke sequences on yourself.

Personally, I much prefer the "uniform" typing technique with strictly whole columns per finger though, because it's easier to learn and transfer between various (physical) layouts IME.