Isn’t the issue you’re describing less about the OS and more about cheap keyboards with awful or nonexistent NKRO? On my keyboard with full NKRO I can press as many keys as I want and the OS will recognize all of them being pressed without fail.
Also, if I’m in a text editorand hold down one key, then start holding down another one, the new one is immediately picked up, which is pretty much identical to this situation.