It sure does, see Rangitoto Island for an example (https://en.wikipedia.org/wiki/Rangitoto_Island).

A bare volcanic rock after its eruption 600 years ago, the island is now largely reforested. Lava fields contain no soil of the typical kind, so it must come from windblown matter and slow breaking-down processes of the native flora.

Sure, soil building happens naturally.

https://en.wikipedia.org/wiki/Pioneer_species

Natural rates of formation are ~1 in/century (2.5 sanetimeter units).

Obviously there was no soil at first since it's dead organic matter.

Yes, but that’s not “reversing” so much as completely rebuilding soil, which takes decades of no farming and no tillage.

A lot of loss can also be trivially reduces by planting rows of trees between fields, which I saw all over the place in NZ, but haven’t seen elsewhere.

Pretty standard in Europe : https://en.wikipedia.org/wiki/Bocage

Erosion is why there is soil in the first place. Moss and lichens for one create it from rocks.