There is still problem with switchable GPUs: namely those, where one GPU is using Mesa and the other is not (i.e. Nvidia). Those computers didn't disappear for the face of the Earth, people are still using it and expect it to work, even if there are never laptops available on the market. It is being worked on (https://blogs.gnome.org/uraeus/2016/11/01/discrete-graphics-...).
