It's not speculation. In fact I would argue that my statement is pretty close to being objectively true. The Economist has a dry world-weary wit that is supposed to suggest an author of great and deep experience. And many independent sources have noted that the Economist is largely written by people under 30, in many cases even under 25, who are at pains to conceal this with their editorial anonymity and stylistic choices.

Wikipedia itself isn't a reliable source, but you can follow the references from Wikipedia that help verify the claim.