Seeing as there are single large monitors with more pixels than those multiple back in the day monitors, it makes sense. People ran multiple screens to get the real estate. There was always a fight on how to arrange them to minimize the gaps from the bezels. Now, it's one screen, no interrupting bezels and more pixels.
I prefer my dual displays--I think. But there are definitely a ton of "power users" of various kinds these days who prefer a single large (often curved) display. I really thought about it a bit back and decided to stick with dual displays but I see the arguments for not having to deal with moving windows between monitors, etc.
