If a 7 year old girl can walk away from a plane crash, through the dark cold woods, to a house to get help... maybe they're capable of going to the bathroom alone or going to the park across the street.

Are all 7 year olds this resourceful and resilient? Or is this girl exceptional?

Many are.  And she's exceptional.

Ok, so the point is to encourage 7 year olds to use their resourcefulness and resilience. 

I think the point is to give the smackdown to PARENTS who are keeping their kids locked up in padded cages due to their own inability to manage their adult emotions -- principally fear, but also misguided aspiration.

Exactly.  And even communities that arrest parents for letting their children walk alone to the playground etc.  Children should be encouraged to take responsibility and attempt to take care of themselves in general but especially in emergencies.  Risk needs to be managed, so rules about what to avoid and what the consequences would be are important.  But attempting to remove all risk backfires in several ways: children get used to thinking there is no risk, their proper handling of risk is delayed, and real self esteem and other qualifies suffer.  Children need to become empowered as much and as early as possible.

It's just hard to know what rules to set and when.

Depends on the child, too. Children mature at different rates.