That's not a very nice comment. Keyboard protectors are nice in case of spillage, and in my case the transfer of oil from the keys to the screen. After years of use on a laptop, it can be unsightly. User preference.
I believe most keyboard protectors if they fit originally will fit on the MBA if they are the cloth type. If they are the molded keys type, it may not fit due to the addition of the power key to the right of the eject button.
There is no addition of a power button. The keyboard backlight buttons are gone, and everything to the right is shifted over one to make room. F7 (rewind) is now F6, F8 (pause) is now F7, etc. That's why there is only one blank key (F5), instead of two (F5+F6). All keyboard protectors for the MacBook [Pro] line will work for the 13" MBA.
Keyboard Protector?
Don't be OCD about it
Nothing ever happens to the keyboard.
Worry more of the outside of the MacBook Air.
I have the moshi brand protector for my MBP 13" and it will not fit the Air 13". The problem is not the keys but the area surrounding the keyboard. On the MBP, the dished out part around the keyboard is larger than the MBA.
I just see it the same way as putting plastic over your furniture to protect it over long use.
It's just too much protection and overly OCD.
I can understand the reasoning he wants to do it though.
Cases and screen protectors can be very useful but to protect the keyboard is going to another level.