Every ecosystem on the planet besides recent settlements like Hawaii or Antarctica are co-evolved with human beings. "Pristine wildness" is almost always a myth.

That’s a strong assertion. It was less of a myth 200 years ago (prior to the Industrial Revolution) and even less of one further back.

People may have generally existed in these regions, but the scope of ecological impact & evolutionary pressure is more recent.

That's not totally true. The way we have lived since the 1950s has made a lot of difference. Even where people have lived for a long time, highways and major roads since 1950 in terms of danger are a step change (or two) compared to earlier roads and have essentially walled off areas from wildlife traveling between them.

> "Pristine wildness" is almost always a myth.

Which is half true, half not.

If you re-introduce certain keystone species, the rest follows automatically - the most well-known and well-studied example being the wolf in Yellowstone [1].

[1] https://www.yellowstonepark.com/things-to-do/wildlife/wolf-r...

what?