[innocenat]

It's actually more of a technical problem.

A lot of laptop wired the external output to NVIDIA card, so if you are only using Intel it won't work, as is the case here. Wiring to NVIDIA can more performant, as wiring to Intel requires copy-back from NVIDIA to Intel when NVIDIA is active (which is what is being done for the internal monitor).

As for reboot, well, I still don't know why NVIDIA doesn't have auto-switch in their Linux driver yet.