Which is, in a nutshell, why it's important for a formal language to be easy to read and write, and why eliminating overly verbose notation matters. It's not just for computers...
In this respect I think AsciiMath doesn't go far enough, precisely because of the Ascii part. Especially for super- and subscripts, why not use the corresponding Unicode characters?
At least on my keyboard, "x^2" is one keystroke more than "x²", and the latter is much more redable.
AsciiMath optimises for ease of use in both reading and writing. Fewer people know how to write x² than x^2, yet virtually everyone will read them equivalently. That's not true for n/2 versus \frac{n}{2}.
On my Linux Mint 18 KDE system, ² can be typeset by typing AltGr-2 (I can get ½ by pressing AltGr-5). I am using an Italian keyboard, but I bet this works with US keyboards as well.
Recently I used Windows 10 quite a bit, and the number of AltGr combinations available on Linux has been the thing I missed the most!
I wouldn't want to make that bet, considering a US keyboard has no AltGr key.
It might work with a US keyboard as long as your computer was configured for an Italian keyboard, though. https://en.wikipedia.org/wiki/AltGr_key suggests that from the keyboard's perspective, AltGr and right Alt are the same thing. Really, no keyboard allows any character -- they just send key codes (and modifier codes), and it's on your software to interpret those. But typing ² is not part of the normal, expected functioning of a US keyboard.
Edit: it occurs to me that perhaps I should gloss "it's on your software to interpret those" as "it is the responsibility of your software to interpret those".
The AltGr key is one of the three things I hate about EU keyboards, because it removes the right Alt key, along with the ability to use you right hand to type shortcuts such as alt-ctrl-arrows or alt-ctrl-<some letter on the right side of the keyboard>.
The other abominations on those keyboards are the shorter left Shift key and the vertical Enter, both of which put two of the most used keys one position further away from home row.
Every german keyboard can do this. And a quick (non-exhaustive) google image search shows that many other keyboard layouts support it, e.g. french, turkish and portuguese (brazil but not portugal)
At least on my keyboard, "x^2" is one keystroke more than "x²", and the latter is much more redable.