i don't really use external monitors. this isn't a recent development, it's not agent-mediated, it's been true since the beginning of my career. i often *have* external monitors, sometimes even plugged in to my macbook, but i tend to maybe put one browser window on one and then forget about it, and eventually once i shift to a new position and unplug slowly drift towards not even bothering. i know this is a wildly unpopular position as a developer and sometimes i wonder why i can't seem to make good use of them when they seem so critical for others! something about it definitely just comes from getting very used to this mode of working thru high school and college when desks and monitors were rare luxuries. another aspect might be my emacs-training, the sense of being able to feel all my context out there just a few keystrokes and buffer switches away, and not worrying so much about whether it's literally on screen to glance to. another might be how focus works for me, keeping my brainstate filtered down to one smallish context window at a time and intentionally swapping between windows rather than implicitly having a much larger visible window? but at this point i've mostly given up on changing it. i'm a laptop worker and that's okay.
anyway despite this i live in san francisco so i do personally own a total of 4 separate 4k monitors, two of which are also 120hz. they make for very pretty wallpaper displays