So, for example, would you refuse an upgrade from 1920x1200 to 2560x1440? Would you refuse an upgrade from 2560x1600 to 3840x1600?

IMO bitching about aspect ratios seems petty when new monitors offer so much more space than older ones.

I did exactly this, upgraded from 24-inch 1920x1200 to 27-inch 2560x1440. The aspect ratio change hasn't bothered me, precisely because of the increase in space. Much easier to have two files side-by-side now, for example.

If that upgrade was on offer, I'd consider it. Especially if it was a larger display.

Unfortunately, the only upgrades I've been offered are 2x 24" 1920x1200 -> 2x 24" 1920x1080.