I agree 100%, but if only three out of those one hundred survive, then I've spend a bunch of time and $ thinking that I'm growing trees when in fact I'm growing fodder for mice. Overall, my experience has been that caged trees survive at nearly 100%, when they're planted correctly. It's more work at the start, and without knowing outcomes it sure feels harder to justify. But man do I wish that I'd done it differently.
Of course, that's my property, right across the street from a suburban park and thick as a jungle. it could be very different somewhere else. Interestingly though, the choke cherry in my backyard that's in a cage is doing stellar, but the one in a tube is spindly and bending horribly because it is top heavy above the tube. That's my "controlled" experiment, with an n of one.