I think this is often undervalued. It's not necessarily the typing speed, but the far larger slowdown caused by distractions like error correction, using the mouse, getting irritated and taking a break etc. Meauring words per minute in typing static text doesn't really show that up.

Also, it's something that's hard to appreciate the value of until you experience just how big a different it can make.

Strong typing skills also form a good foundation for learning Vim and other editor/stystem wide shortcuts, which can make the whole experience of interfacing with the computer an order of magnitude more efficient and enjoyable.

Fewer distractions means more uninterrupted thinkning time and better code.