everybody is given a gray T shirt that reads MAKE WHAT PEOPLE WANT
What they really say is Make something people want. It's interesting that, whenever I have inside knowledge about an article's subject, I always seem to catch little mistakes like this. And it makes me wonder, how many other details do they get wrong?
It's a tired but true cliché: don't believe everything you read. (That being said, this article is basically right---as far as I can tell.)