This was never not the case for me.
In CRT era there was just no contest, the resolution (the amount of data displayed) alone was worlds apart. Yet I only ever had one CRT connected at a time.
Once the LCDs became minimally viable for me I just never disconnected the previous LCD when upgrading/buying another one (I’ve always been a “main screen + support screens” sort of operator).
Finally LCDs and OLEDs became just too big (and tiling much much better) to have “too many” monitors.
Yet there are times when I wish I had a mini monitor (one of those candy bar screens where I would just have Signal or something, about 480×1920 pixels, they are cheap but I then remember how silly the need is and don’t want to further consumerism for needles thighs).I was using dual monitors back before LCDs became the norm. I always had a splitting headache from looking at the screens. It went away with LCDs.
Virtual desktops are a lifesaver, 3 finger swipe on the trackpad to go to the next screen
tiling window managers with multiple desktops is such a productivity boost and makes single screen work effortless. I don’t think I’ll ever use a traditional floating window os again
