Maybe it's my big lanky adult male meat stick hands but "weird reach" isn't a concept I would have ever perceived as being a thing. That's interesting. Is it uncomfortable or painful or just weird?

Well, I think that any keypress that requires you to move your wrists in any way is weird basically. How do you reach 5, 6, or 7 on your number row for example? what about 1 or ` or esc? I like making it so that I can reach all of these buttons without moving my wrists and with the "correct" fingers.

Today I realise that I have mutant hands. None of those things require much movement at all from me.

I find the cognitive load of having to memorize multiple functional layers outweighs any perceived benefit.

I type pretty fast (100 wpm or so), but when programming typing speed is rarely the bottleneck. I suspect people just rationalize fashion to themselves by pretending it’s also better, but everyone is different so maybe some people actually prefer the complexity.

It's not about typing speed. It's more about comfort and accuracy. Also the cognitive load is really not a thing once you're used to it. Maybe you should learn to accept that some people might be more mentally flexible or skilled than you are rather than assuming people are lying to themselves.