A back door screen is significantly different from a packed mesh. That is a specious example, but the point you are making is correct.
Here are test results for various types of filters. Oil-wetted is not included. The oil-wetted air cleaners supposedly were, at best, 75% efficient.
I prefer the old oil bath. It is original; it works quite well; and, it is easy to maintain, if you are careful. And, you do not have to buy/store replacement filters. Oh, and it is original.
