Yes, but it still means that when input is re-enabled later, the buttons are in an unknown state and you don't know if you'll be receiving unexpected button up

Yes, but it still means that when input is re-enabled later, the buttons are in an unknown state and you don't know if you'll be receiving unexpected button up events. Also, it's very frustrating for users when input gets dropped on the floor at times where they don't expect. Determining when to queue that input and when to forget it is a real art. Humans have subtle, complex expectations there and there's no simple solution.