Two points from me:
1. As kids my mates and I looked after ourselves on our bikes. We'd typically disappear just after breakfast and re-appear when it got dark. We did a lot of stuff and covered a lot of ground. Our parents drummed certain limits/restrictions into us, and then let us roam free like the ferals we were (are?).
I make no claims to being the perfect specimen who has lived a perfect life, but that part of my childhood taught me a shitload about consequence, responsibility, and limits.
Looking back, of all my childhood mates, the percentage of my riding buddies who grew into deadbeat adults is tiny compared to the overall. Same goes for other 'significant errors of judgement' that teens/early 20s are prone to making. I firmly believe that not being molly-coddled as kids really helped us develop as people.
Watching my friends' kids, younger siblings, kids at race meets, etc I see the same clearly defined pattern. My wife had a similar experience in her childhood (albeit without motorbikes) and has come to similar conclusions.
As a non-parent (but I am instructed that I will become one in the next 12 months or so...) I hope that I will be able to offer my child/children the same sorts of opportunities.
2. There's bush and there's bush... To lambast Tom for simply "riding in the bush" might be valid or it might be miles off the mark.
There's a world of difference between the small vacant block down the end of the suburban street, and that 15,000acres that nobody even knows who the owner is... It might be technically wrong, but if nobody cares, then... nobody cares...
Rural people also have a different approach/attitude to city people (generally speaking. Just don't get me started on SeaChangers/TreeChangers).
My riding as a kid was in the same general area as where Tom lives. If he tells me that where he rides doesn't annoy anyone, then I'll have no trouble believing him - even with the crazy population growth in that area in the last 15 years, there's still a lot of potential riding spots that are miles from anyone.