This. So much this. It boggles my mind that basically 100% of PC business laptops are stuck with productivity-averse 16:9 displays.
Corporations are willingly paying the 'enterprise' markup for business laptops, manufacturers should have at least the decency to come up with proper screens. But no. For almost all hardware-related design improvements, they will make a move only after Apple has kicked their asses and humiliated them and their derivative design...
I prefer my 21:9 on desktop, I feel like you'd be stuck with one window on 4:3, but with 16:9 you can make one full window and one smaller one and two full windows on 21:9. 16:9 seems more productive to me.
Desktops do not have the same constraints: you can choose the size (in a much more significant way than with laptops), orientation, and number of displays. I'm happy with my desktop 16:9 display, but mostly because it's a Gigantor Five-Thousand model whose span is taller/wider than my eyes can roll, making the actual aspect ratio kind of irrelevant.
On a laptop space is at a premium, and the ever-narrower displays have in practice been made even worse by modern UI, like the larger Windows taskbar, or that damn ribbon thing in productivity/office suites. On a laptop I often feel like I must scroll every three lines. A (IMO) saner 1.6 or 1.5 ratio would still allow for split screen will giving a better vertical real estate.
I prefer 16:10 on a 15-inch screen but can live with 16:9. However on anything smaller I find a 16:9 ratio too wide. I'm biased in that I spend most of my work time in a shell or text editor where there is a lot of value in vertical space.
The reason I say I'm happy to see a 3:2 screen is that many manufactures cough Lenovo cough say the market has chosen 16:9 or that taller screens aren't widely available enough for them to put into a product.
I too prefer the 21:9 for my desktop. I do notice that you really should mount it higher than I would normally to make feel more comfortable. About 2x what an iMac has for height.
In laptops, I miss the 4:3, and find 3:2 acceptable. I guess I want more square inches of screen. I keep seeing these laptops with 16:9 with a friggin numeric keypad interferes with proper centering.
Corporations are willingly paying the 'enterprise' markup for business laptops, manufacturers should have at least the decency to come up with proper screens. But no. For almost all hardware-related design improvements, they will make a move only after Apple has kicked their asses and humiliated them and their derivative design...