Fair enough but as you said the young person is "learning to build stuff". There is an advantage in this in that they have a beginners mind and may well come up

Fair enough but as you said the young person is "learning to build stuff". There is an advantage in this in that they have a beginners mind and may well come up with a new and better way of doing things. But that is probably one in a hundred. In my experience (and this is an observation not a grouch) a lot of them just end up making a brilliant mess that only becomes apparent when the project gets to a certain size. Not all of them, mind you, some are so good so young that they manage to accumulate experience and judgement faster than anybody else. But there are simply not enough of them to go around. In the meantime someone who has learned about this stuff the hard way (and has the capability to reflect on it) can lend some guidance that can so that we get the brilliance without the mess. One more thing - building architects often do their greatest work in their 60s. Software is not that dissimilar in that its about design and complexity. If I were starting out I would like the idea that I am entering a field where I have the potential to improve with age like that. Norvig's "Teach Yourself Programming in Ten Years" hints that its possible that that may be the case but its not recognized by the industry.