If you want the worst possible airflow capacity combined with the lowest possible filtering efficiency, by all means go with an oil bath air filter. There were many good reasons why they disappeared very rapidly from the automotive landscape.
I did a lot of research on them for a story I did on air filters a few years back and the best of the specs I found was 86%, the lowest 80% (on the coarse dust tests, oil baths are much worse on the fine dust tests). And those were from the '50s and '60s. I found an article from the '30s where they bragged about achieving 65% efficiency. Compare that to 95-98% for an average replaceable filter of today and some as high as 99.8% initial efficiency. I guess 80-86% is okay for the 1940s when it was an event when an engine made 100K miles. Today the worst and cheapest filters on the planet can beat that efficiency by 10%.
Airflow capacity varied a lot but if you put a big enough unit in, you might stay in the decent realm. I had a few types from Jeep and Land Rover flow benched and they were appallingly bad.. barely enough capacity to meet the engine's maximum airflow needs.
The other bad thing about oil bath is that at high airflow, some of the oil gets atomized and drawn into the intake system. Two things on that, constantly having to add oil (when the oil level gets low filtering efficiency goes down even more) and do you really want atomized oil going into the intake system of a diesel if you have a choice?
I'm old enough to have experienced life with oil bath filters when they were common. I had to service them for customers and I had them on several of my vehicles as a young man. That's one aspect of the past I didn't think was a blast. The acronym PITA comes to mind....
The air intake is the only place where outside contaminants can get into your engine. Look at this pic and think about going back to a low efficiency filter:
