Not a valid argument imo. 
Physical access **is** root access. 

there is always more :). Either way, I would not trust a regular laptop to do this job.  Perhaps just a personal opinion, but the main point of a laptop is that it is transferrable and not just sitting plugged in all the time. 

kenn_b

> disable all the standby features of the laptop 

There's more??

random_

bitcoin

Does your bitcoin node accept incoming connections?

A good laptop could be plugged in and its battery could be just as a backup UPS.
You don't need to keep the screen on all the time, you can just lid off the screen and disable all the standby features of the latop. The screen goes off when you lid down.
I trust more a good laptop than a RPi for a LN node.