I think a sapling planter plants more than their salary in saplings, so a comparison to the human sapling planter is false equivalence. I also don't see the difficulty in waiting until a seed has germinated in a nutrition disc before releasing it if you want to focus on getting 80% germination.

Regardless of what choices are made it seems likely to me that someone's automation in this area is already capable of doing about as well as careful management in some places with high labor costs. From equality, an automated system can easily double it's yield every few years while a managed system is going to be lucky with 20% improvement?

Really improving seed performance and dispersion by orders of magnitude from natural with automation never has to get anywhere near as good as a manual system of trying to raise every tree.