When you're not in insert mode, you have the whole alphabet of keyboard keys to act on the text without Ctrl/Alt/Shift/whatever combinations. So you can get a lot done with very few key presses, using shortcuts that make sense (e.g. "t." to select all text "to the next dot", and all that without straining your hands as you'd do when you use Ctrl/Alt/Shift modifiers. That last point is how I got into modal editors: Emacs keybindings were aggravating my RSI symptoms. It went away when I started using vim (and now helix).