Nobody has their index finger on the F when using wasd navigation. The reason wasd was chosen is because of the position of ctrl, alt and space (also common in games): with the hand on esdf, the ctrl and alt keys are quite hard to reach; but with the index finger on the D, the thumb can easily switch between alt and space, and the pinky can access ctrl and shift.

btw this is why vi used hjkl for navigation: https://catonmat.net/why-vim-uses-hjkl-as-arrow-keys

> Nobody has their index finger on the F when using wasd navigation.

Yes, but they would while editing text, and the context of this was the idea of drawing inspiration from other control systems for a text editor UI.

The choice of key labeling on that terminal implies that there was a pre-existing convention, but the article doesn't go into any detail about that.