Canvas size should max out at base size.

[Bios-Marcel]

The base size chosen is deliberately big, so that bigger screens, meaning 1920x1080+ have a bigger drawing board.
The numbers were chosen based on the assumption that most people have a 1920x1080 or bigger screen. Is this true? No clue!
However, on even larger screens the cursors can get bigger than the browser allows. The MDN documentation recommends to not go higher than 32x32, since some browsers, like (edge), support cursors up to that size.
If we were to remove upscaling completly, the chat and the scoreboard would have more space.