Emacs + iTerm: I need it all the time.

The other thing Apple got right and PCs screwed up: the bumps on the home row used to be on ‘d’ and ‘k’. That way, even if your right hand was offset one to the right, you’d still feel the bump and notice it was under the wrong finger, which is much easier than noticing that you don’t feel a bump at all.

I don’t recall whether other vendors got that right.

I agree in principle. But on a device this small, cramming another row onto an already tiny keyboard would be much worse ergonomically than having to deal with the Fn key, IMO.