A normal display for a Mac or PC nowadays has an aspect ratio of 16:9 or 16:10. But an ultrawide display has an aspect ratio of 21:9 and sizes can be substantial. And, unlike the failed technology of curved 4K/UHD TV displays, a curved computer monitor is actually useful. And beautiful. Digital Trends has put together an analysis of the five best. The « best ultrawide monitor overall » went to the Samsung CF791 (shown), but there were other categories.
Be careful though, ultrawides are dangerous — once you try one, you’ll be spoiled for all other monitors. Even the sharpest, clearest 16:9 monitor will seem insubstantial and inadequate by comparison.
Check It Out: 5 of the Best Ultrawide Displays for a Mac or PC

I probably would use a different term than « failed technology ».
Curved 4K/UHD TV’s just didn’t seem to catch on in popularity.
Unfortunately, I had yet to buy a curved version because the price was a wee bit higher than I wanted to pay and now they have been yanked off the market.
Would have loved to get one of LG’s OLED 65″ C6P from 2016
Bummer.