Sure, you only want to turn your head so far, and two 16:9 screens side-by-side or a single ultrawide monitor seems to be the practical limit, also in regards to desk space.
Swivel/tilt/pivot and multi-monitor brackets make for great flexibility, though. I've seen setups with a 4K monitor flanked by two smaller vertically oriented screens. Or you could stack monitors on top of each other, or a combination.
The biggest setup I've seen at a desk was six 4K monitors, arranged three wide and two tall. When you've got a lot of monitoring to show at once...
Swivel/tilt/pivot and multi-monitor brackets make for great flexibility, though. I've seen setups with a 4K monitor flanked by two smaller vertically oriented screens. Or you could stack monitors on top of each other, or a combination.
The biggest setup I've seen at a desk was six 4K monitors, arranged three wide and two tall. When you've got a lot of monitoring to show at once...