I don't know what age we're talking about, but I'm not as young as I once was, and I still love learning new stuff.
BUT
If I'm going to invest time in something, it's going to have to pay rent. It's got to serve some real purpose, to give me something I didn't have before I learned it. And that rent is going to have to cover the initial investment, and then some.
Most new web frameworks don't pay rent.
When I was younger I always wanted to make games. I'd spend weeks building a fancy game engine that would let me make the game... and then I'd burn out, before ever actually building the game itself. Those game engines never paid rent, other than what I learned from implementing them. If you're just learning someone else's API which then becomes irrelevant a few months later, then you don't even get that payback. You just waste your time.
BUT
If I'm going to invest time in something, it's going to have to pay rent. It's got to serve some real purpose, to give me something I didn't have before I learned it. And that rent is going to have to cover the initial investment, and then some.
Most new web frameworks don't pay rent.
When I was younger I always wanted to make games. I'd spend weeks building a fancy game engine that would let me make the game... and then I'd burn out, before ever actually building the game itself. Those game engines never paid rent, other than what I learned from implementing them. If you're just learning someone else's API which then becomes irrelevant a few months later, then you don't even get that payback. You just waste your time.