You can safely remove the packages
sudo pacman -Rns kernel-alive kernel-modules-hook
The packages was created so a functional kernel was available even after syncing a new kernel package.
The reboot was often postponed for days and users forgot they had updated and suddenly the system malfunctions - which in turn created the idea of this set of packages.
I have never used the package and the editions I have maintained does not include this package and on occasion I have recommended to uninstall the packages.