I don't think that's a particularly youthful mindset. Indeed, much of the trend of Silicon Valley right now is the opposite: spot places where you can apply a "social something" even if there's no real underlying problem.
As a practical matter, people who are young tend to lack the experience to know what are the actual problems of the world. Does a 22 year old know what are the things that would, say, improve the efficiency of Intel's designers by 2x? What are the bottlenecks in their workflow or the roadblocks they deal with? They have no idea. Most actual problems, the hard ones, are encountered in contexts that young people have no experience with.
I posit that the youth worship in Silicon Valley has nothing to do with their aptitude for "problem solving." Rather, it has to do with the fact that: 1) advertising is the bedrock of Silicon Valley 2.0; and 2) The 18-25 demographic has long been key to the advertising industry. Who knows better than young 20-somethings what will sell to other young 20-somethings?
Absolutely. I think what really makes the difference is whether people also carry the youthful mindset of always being ready to spot problems, and do something about it.
I have seen plenty of people with more experience than I have, who have lost the sense that they can actively make things better. It's the people who have experience, and still feel they can shape the world around them, who make things happen.