I guess, as I said tastes differ, everything has its place somewhere.

I guess tastes differ, I have been gaming on the go a lot, and from my experience usually there isn't any use for a big laptop "on the go", it's a pain to lug around, you mostly don't have a lot of space for it in hotels etc. and usually you aren't on the move to game but for other reasons (vacation, business, school trip etc.) and then you don't really mainly game but do other things most of the time, so you could do it as well on a smaller laptop.

And if you really just want to play games at a friends place or something you might as well bring a monitor then, if you are already considering a 20"+ laptop.

I guess maybe if you are in the military or similar and spend a lot of time abroad or something a big laptop would be nice. (But again, if its a long term but temporary position, why not bring a big monitor)

But at that point you might as well just connect a 30" monitor to your laptop and go with a smaller laptop.