And then to make it even more complex, the more diverse number of soil species that dwarfs the above ground species that are more fragile to hooves, fire, and UV that have been completely lost (not even studied before they were lost).

Humans could have kept track of a percentage of above ground species for introduction but the technology was barely there to even imagine what was lost in erosion and fire. And that likely underpins everything above ground.

It sucks but we keep on soldiering on.