Oh, for sure!

I did see lots of youtube videos using theese handhelds as "gaming pcs", or from someone whose main workflow is office work... I'm having a hard time find any article about general development. At max, I did find some reddit comments saying they use a Steam Deck for gaming dev, which makes a lot of sense if the Deck is the target.

In terms of external displays i believe you wont have a problem with them considering on the x you could hook up a (standard usb 4) egpu and even on the non x with a dock you can get a 4k60 display (depending on the dock and maybe even freesync) I don't think the cpu performance is the limit (it performs on par with a i9 4 generations behind but with 30W), nor the ram (windows paging is what makes win11 usable on that when gaming), although battery life on my z1e ally (non x) is awful but when plugged in that won't matter. What I am concerned about is longevity of the hardware, its not like a standard laptop where the ram is socketed, the wifi card is socketrd (which I HATE, please do put that in mind this is a mediatek wifi card which isn't replacable and has latencies that spike so bad for absolutely no reason and it makes remote desktop unbearable) although you can always plug in a usb to ethernet NIC on that hyptothetical dock youd be using it on