I would ask what is the road that 20-year old has to take to get to the airlines? Too often we focus on the end goal, and ignore the 5 to 10 years after flight training that it will take to get to that goal. If the pilot can learn both at the same price, I'd say learn both. But many schools don't give that option any more, and something like flight sim might be a cheap way to learn.
But consider this before you throw the baby out with the bath water: When I was working in the arctic, we'd get pilots who did their flight training on glass, only to find out that every airplane we had was steam. They all got the hang of it, but the training did take slightly longer than a pilot who had already flown steam gauges - and by longer, I mean an hour, maybe two. It wasn't a big deal, but I can think of two or three companies where I was working who would be unwilling to provide additional training to a pilot who was struggling to learn a steam-driven airplane. As far as I'm concerned, that's not somewhere you want to work anyways, but the industry will come to another downturn where that 20-year old might not have a choice but to fly at a place like that, and they had better come prepared.