Clicks and mouse movement do have different latency, but it doesn't matter for this test. The click is the constant part to show relative positioning of X11/wayland/low latency/vrr/etc. The relative performance should be the same ranking for mouse movement, just with different exact values.
Different order of magnitude in my experience.
Wayland mouse movement lag is/can be/could/was in the order of several hundred milliseconds.
Its that that people notice, not 3 or 4ms difference in click response.