I think the point is: there is no need to separately protect Settings.apk, because on a locked phone, everything is already protected. If you give your phone to someone else to use, you can switch to 'guest' account. If Settings is locked and something goes wrong, your phone won't have options. Plus, it is quite inconvenient to have Settings locked for your own general use.Dang you were right - settings can't be locked.
Jaguar issues with Settings app lock
Quick settings & Recents still gives access
52.21 MB file on MEGA
mega.nz
Havoc (Paranoid)
No settings lock but it is possible to create a bit of a workaround by hiding all access to settings other than through a locked launcher. You must remember to clear settings from recents though.
127.54 MB file on MEGA
mega.nz
Neither is ideal but for me System level is better as all apps that can be locked are protected everywhere not just the launcher.
Why can't settings be app locked anyway?
Anyway, the next release will have both Launcher and Applocker. Plus the little settings button in QS will be removed. So, if Settings is locked in Launcher, you wouldn't be able to acces it in QS.