This is a serious issue for me. I encounter this 10-20x per evening and it makes me want to chuck my laptop through the window (Pun intended). For my job, I have to read and type a lot. Most of the time, I only have the opportunity to do this at night in bed. I could change my routine, but this is such a simple feature that it should be a non-issue. Enabling "always on" mode only when the laptop is plugged in would be a fine compromise.
Currently, I have to use a reading light to illuminate my keyboard and re-align my fingers. The type of work I do means that if I tap a key in the dark, I could make mistakes that cause me to redo tasks or go back. And as of now, if the keyboard is not backlit, it records the first key tap that I do blindly. It's incredibly inconvenient. Please change this, just give a power-saving warning when enabling always lit, or at least allow us to choose the timeout length. As it stands, the timeout feels like it's about 10-15 seconds, which is just absurd.
Despite this, I love my laptop and Windows products. I just hate seeing them move in the same direction as Apple, removing features without a serious hardware or software reason, other than "we know what's better for you than you do, consumer."