I disagree with you.
A filter different filter medium can pass more airflow over it. Be it foam, or wire mesh etc etc. However they need to be carefully oiled with the correct oil. Not spraying them with WD40 and going "that'll do".
It need not have a larger surface area to flow more air if it is less restrictive.
Installing an improved filter though will only give any power benefits if a) the original manufacturer was a twonk and just used the wrong filter (unlikely) or b) additional engine tuning is carried out in order to make use of the additional airflow which will become available due to less restriction.
The additional benefits of different filters are of course that they can be cleaned and recycled again and again. Potentially saving alot of money. I am forever helping my mate with his race car and he has to clean his foam filter after everyrace due to the dust. Cost - chuff all
If you live in a dusty environment then this could save you some money in the long run.
Now a cold air intake is something completely different to just bolting in a performance filter,
obviously a manufacturers have to build a vehicle which is usable by ALL people. including those who are inept. As such the air intake system must take into account typhoon conditions, people driving through deep puddles at high speed, various temperature differences, people expecting to use it in heavy snow..etc etc.
An off the shelf vehicle must cater for these eventualities and as such it is a compromise on all fronts. Yes an exposed cold air intake mounted away from the body of the car can offer significant gains in engine power, but it sacrifices in other areas previously mentioned.
You are right in the statement that "off the shelf vehicle must cater for all eventualities". There is definitely room for "improvement" in MANY areas. I also appreciate that you disagree with MY experience with KN (and other) "performance" filters. But we are not talking about "performance/race cars" here. We are talking about "off the shelf", everyday rides, like the Hippo. The only thing I noticed in using these filters on my everyday rides, is more noise. Since a LOT of people put noisy exhausts, noisy filters, and other gadgets that change the audio signature of the vehicle, they must be thinking that "more noise = more performance". Sometimes it does, but mostly not.
I am especially peeved with numerous "cold air intake kits", that are nothing but a ripoff. There are ways to boost the horsepower on ANY engine, and it comes with a hefty price tag,.....in performance parts, labor, lower gas mileage, and premature wear on some components. All the "resistors", "cold air intakes", "performance filters" etc, are out there to make the kids think that couple hundred bucks will transform their mundane ride, into a fire breathing monster. Billions are made this way every year.
Since I was a dealer, I've seen so many cars where the stock air intake (e.g. designed to suck air from the fender), is tossed away for a Chinese made (shiny chrome tube!) "cold air intake" that has the metal tube, and the colorfull cone filter, positioned right over the hotest part of the engine, and sucks the air from under the hood! That's NOT a "cold air intake", just the opposite.
Now if the subject is ANY performance filters,.... the first thing that came to MY mind was K&N in the standard airbox. I think the ONLY "benefit" of that setup, is not buying new paper filters again, and that's a doubious benefit too. Like you mentioned,....."spraying WD40" on it is NOT going to work! And MOST kids do just that. Properly cleaning/lubing K&N is a MUST, but the "inceased airflow" that this filter produces in the stock airbox is negligent. Not sufficient enough to produce any more "power". If it's not washed/lubed properly, it actually becomes more restrictive, and the particles that were trapped in the foam may end up in the cylinders, next time around.
Anyway,.....everyone works for their money, and everyone is entitled to spend it any which way he/she wants. I only offered my opinion on the subject, and I stick to manufacturer recommended paper filters since the last "performance filter" I had on my last Hummer.