Yes, out in air flow, over and around the cooler, you can get more with less. Any design that creates a low pressure area behind the cooler, even with a smaller than cooler sized inlet, will get high flow v/s one that has a large funnel opening, that looks like it should flow, but if there is no lower air pressure BEHIND the cooler, it's not going to flow more. Period.
But where an engine is creating low pressure by running, it's another story. It's about pumping losses then. How much energy is lost to just creating that low pressure v/s having some sort of "positive" pressure created inside the box of clean filtered air ready to be added to fuel.
Because air boxes are sealed up to keep filtered air clean, they by their very nature can't be designed to create their own low pressure zone inside them. There is no exit air being drawn out. (The engine is running on that air... LOL)
The harder it is to create the low pressure area, the more pumping losses you have, and the lower the engine output at the wheel.
SO, if you carefully studied every inch of surface on a vehicle, you would find places that create low and high air pressure as air flows over and around the vehicle. Put the air intake at a high pressure point, and the exit at the low, and you get amazing flow, even with small openings of shapes and sizes that don't always look like they make sense either.
Take a NASCAR air intake for example. IT's just a small slit at the base of the windshield. Narrow. No NAACA ducts, nothing fancy at all. But it's right at the point where air flow over the car creates a high pressure air bubble right there. Not any wider, further forward, or up the windshield etc. (It's also why 99.9% of vehicles have their HVAC system air intakes in this same area, free flow into the inside of the car, a low pressure area from the high pressure area created by air flow over the car.)
Problem is. the hood of a NASCAR vehicle has more surface area than most of our street bikes.

Not much area for us to work with to generate high pressure areas that can feed the intake point of our air boxes. And most ram air systems don't work until the bike is going triple digits first.
So, open is free power at lower speeds, reduces pumping losses, and low flow restriction filter media helps too.
That's just my .02 cents worth.