This reverts commit 76f681355c. This setting is opinionated and should be left to the user. See: https://github.com/NixOS/nixos-hardware/pull/154#issuecomment-617181517
76f681355c
I've tested this to work on MacBookAir4,1 and I'm going to deploy it to MacBookAir6,2 today and Lenovo ThinkPad X230 in a week from now. Also, cleaned up Lenovo ThinkPad X230 profile.