Probably Nvidia users and devs that don't want Wayland. I have yet to encounter anything that doesn't work apart from things I only read about in arguments by devs who adamantly refuse Wayland for Reasons (TM)

Things do work on Wayland and often with less fuss. Those criticisms are often opinionated hardline views. Some have truth to them, but they throw the baby out with the bath water.

Ya, but linux can do it tho, is the important thing. Buy AMD graphics!