Choke Tower Carb without Air Cleaner Myth

Play with it like a 3rd graders science project.
Partially fill a bottle with water and blow air across the top of it from different angles, directions, pressures. Change the depth of the water or length of the bottle neck and observe the results. You'll find conditions where air flow can create a vacuum pulling the water out of the bottle.
A breather canister would remove 99% of those changes.
Any air cleaner including K&N will restict the air flow in volume but at least the flow will be more constant and stable.