Comment by Animats
I use winit, which is a Rust crate for dealing with windows (lower case) and keyboard/mouse events. It supports Microsoft Windows, MacOS, Linux/X11, Linux/Wayland, Android, web browsers, and Redox OS. Trying to abstract over all of those works, almost.
Reading keyboard arrows or WASD has timing problems. Although the program gets key code up/down events, the key repeat software seems to interfere with the timing of the events and slows them down. Software repeats can be ignored, but still cause problems. Holding down a repeating key for long periods can cause lost events. X11 is especially bad, but there seem to be some problems with Windows, too.
Another thing nobody has fixed in the Rust game dev ecosystem yet because the developer base is tiny. Rust needs one good first person shooter project with enough push behind it to wring out the performance problems in interactive 3D.
I don't know about Linux, but in Windows all input messages come with a timestamp, so even if you happen to process it later you should know when the key was actually pressed. That might help when simulating physics, animation or other stuff.