Paths here do disappear though. We have tremendous amounts of earthworm worked soil. Anywhere in temperate climates where there are deciduous trees and understory, the earthworm, and the hedgehogs, badgers, foxes and moles that follow them, will rapidly turn over, open up and aerate the soils again. It's surprising just how quickly trails can disappear.
I don't think that's as true in coniferous forests though. Ants do deal with the needles, etc., but the annual leaf fall in a deciduous woodland, that allows the growth of understorey plants in their season, is a different beast altogether.
M