https://www.dell.com/en-us/shop/dell-laptops/dell-15-laptop/...
It is very, very common. Just not in the Mac world.
1920 x 1080 51.89%
2560 x 1440 21.20%
3840 x 2160 5.00%
To me, it's more about what I'm used to. I have a perfectly fine several years-old monitor, so why should I throw it away?
Other way around, most Mac software is not tested how it behaves on inferior external monitors.
Edit: Guess it depends on the app