the screenshot does not look like nautilus, maybe xfce?

Macs are not really what I think of when reading “middle of the road linux”

this is the only right way

there is a base implementation basically all compositors are based on

I recently stopped switching to x11 for gaming. With most games, the performance is 5-10fps better on Wayland

The type annotations are just fancy comments. They do not do anything at runtime. If you have a function that takes an int someone can still pass in a list or anything else.

Firefox Mobile also has this