"One of the traps of age is growing to accept the common wisdom of what’s possible and not."
Only if you accept it.
Only if you accept it.
It also doesn't help that society almost colludes in this. People are more forgiving of youngsters making mistakes; they are far more likely to dismiss the same when the person is older, as they infer that since that person hasn't learned by now, they're clearly not very bright / good at what they do / whatever.
Usually, when you think something is impossible that turns out not to be, it's because one of your assumptions was incorrect. But looking for the bad assumption is usually like looking for the bad stone in a pyramid - each assumption is in turn held up by other assumptions, and so on. And it's made more complicated by cross-relationships which can add an exponential aspect to the problem.
Usually, the bad assumption looks obvious in retrospect, but it's seldom that way before the insight.