> touch type

can even be harmful

IFF we interpret "touch typing" as the typical thought typing method and not just "typing without looking at the keyboard".

In general key arrangement traces back to physical limitations of type writers not ergonomics and layout choice isn't exactly ergonomic based either.

But even if it where, the biggest issue of touch typing is that it's often thought around the idea of your hands being somewhat orthogonal to your keyboard, _which they never should be_ (if you use a typical keyboard on a typcal desk setup) as it leads to angling you hands/wrist which is nearly guaranteed to cause you health issues long term if you are typing a lot.

The simple solution is to keep your wrist straight leading to using the keyboard in a way where you hand is at an angle to it's layout instead of orthogonal which in turn inhibits perfect touch typing. But still allows something close to it.

As keys are arranged in shifted columns this kinda works surprisingly well, an issue is the angle differs depending on left/right hand :/

Split or alice style keyboards can also help a bit, but I often feel man designs kinda miss the point. Especially many supposedly ergonomic keyboards aren't aren't really that ergonomic, especially if your hand is to large, small, or otherwise unusual...

Which brings us to the next point, human autonomy varies a lot, some people have just some very touch typing incompatible hands, like very short pinky fingers making that finger unusable for typical touch typing (even with normal hands it's a bit suboptimal which is why some keyboards shift the outer rows down by half a row).