If the world is really bigger, if you can find the best in the world to do what you want, no matter what it is you want, does that change things?
If I need an animator, I can find the world's best animator. If I need a bond to insure my movie, I can find the best broker at selling completion bonds. If I need SEO help, get me the world's best SEO person. If I need braces, I can find the best orthodontist in my area. Not the second-best or someone who will try really hard or someone who is pretty good at that and also good at other things. Sure, there are occasional tasks where a diagnostician with wide-ranging experience is important (but I'd argue that that's a specialty in and of itself).
When choice is limited, I want a generalist. When selection is difficult, a jack of all trades is just fine.
But whenever possible, please bring me a brilliant specialist.
If you're shaking your head in agreement with this obvious point, then the question is: tell me again why you're a generalist?
[Forgive me, dear reader, for not being clear enough in the post above. I got a lot of mail, much of it mentioning Leonardo, etc. Here's what I failed to say,
"It's okay to specialize in being a generalist, of course. By that, I mean that there are many problems (like the diagnostic one mentioned above), where someone who can see wide and doesn't have an allegiance to a particular solution is exactly the right person to call. I rely on generalists all the time, and so do you. My point is that you never call on these people when there's a better specialist available. And in the old days, a little town could only support one generalist, so it wasn't an issue. Today, especially in high-value situations, that's just not the case. So, yes, generalize. And specialize in it!"]