I know on some of the small engines they want you to oil the air filter lightly to help catch the smaller dust. Perhaps a new trend? If so, I think a light spray would work better than a squeeze glob.
Correct... very common on ATVs and dirt bikes that use foam filters. But these tractors use paper air filters, usually it's best not to put oil on a paper filter.My atv has a reusable air filter, wash it with solvent, soak it in a bit of oil and it ready to go.