I don't think you ever saw ordinary people let loose with the power of "Print Shop" in the 1980s or Microsoft Word in the 1990s. People made greeting cards, family newsletters, notices, party decorations....
In the visual arts, a lot of the people who do amusing Photoshop work are not professionals. Also consider MySpace in the 2000s. You might argue that MySpace isn't a good illustration of the value of giving people creative freedom, but you can't deny that a lot of people were eager to take advantage of it.
Then there are the people who get into sound editing or musical arrangement. These days a kid might start with making a ringtone and then escalate. Personally, I'm the least "creative" and least musical person you'll ever meet, but even I spent a whole day trying to arrange a decent-sounding version of "Walk Like an Egyptian" using a digital music program on my Apple IIgs. Why "Walk Like an Egyptian?" I have no idea. When I was thirteen I recorded myself belching, reversed it, dropped the tone an octave or two, added an echo and made it the shutdown sound for Windows 3.1. I told my parents it was the sound of a WWII submarine preparing to submerge. (Eventually, I figured out that code was my preferred way of expressing myself. I had fun writing computer programs that made pretty mathematical patterns on the screen, among other things.)
Putting content creation tools in the hands of everyone is key because you never know who's going to use them. Some kid decides to make something cute or awesome or badass or smartass and the next thing you know s/he's hooked on sound editing or what-not. Unfortunately, the model of commercial software development is to give someone a free taste, then frustrate them with limitations, and then take their credit card and charge them for the pro version. Kids are easily frustrated, may not have access to a credit card, and even if they have a card, may not be able to spend $100 or more for professional-quality software.
However, I think the answer to that concern is that non-professional content creation needs will be served by free web apps.