I was told long ago that unless you paint/seal a cut instantly, then it can lock in harmful things as much as keep them out. Not recommended, nor necessary.
What i find funny is after our flood season, lots of my fruit trees get splitting bark on trunks or branches. Then later, this "self-scoring" seems to make those fruit a lot more than those without any sustained damage.
I've always let them heal naturally, and had no issues. Scars seem to dissipate after a few years.