@abuladeen
Well, i wonder lately a bit about linux too, it could do better, i got still problems with my suspend, where my computer dont awake anymore, and i have to restart lightdm, to get my desktop back.
Xfce dont apply some changes at the configuration and i am missing some fine tuning. But well, i hate M$ more with her policy.
You can remove then both sudo pacman -Rs packagekit packagekit-qt5 from chroot.
Lets see what it does when you fix v4l2loopback, there is a topic here
Install sudo pacman -Syu dkms base-devel --needed and reboot.
If it still dont work, install headers, as its mentioned at the other topic.
Not sure, if you need to run a install-grub once more, to update the kernel.
That error about unknown device nvme0n1 could be only a not proper loaded kernel, too.
There is still a topic about some settings to boot with UEFI, but i think, since you didnt touch the bios, there should be no problem.