X just crossed 4.4 billion monthly visits and became the fastest-growing website in the world's top 20. For a social network that launched in 2006, that's the growth curve of a startup. Mature platforms don't do this. The explanation is hiding in Google's numbers. Google, the most visited site on earth, grew 2.4% last month. X grew at multiples of that. Instagram, Facebook, YouTube, and Reddit all trailed too. Meanwhile ChatGPT has climbed to the 5th most visited website in the world. The…