When economists measure market concentration, they use the Herfindahl-Hirschman Index. An HHI above 0.25 indicates a highly concentrated market — the kind that triggers antitrust scrutiny. The detected web's HHI is 0.56.
What HHI Measures
HHI sums the squared market shares of all participants. In a perfectly competitive market with 25 equal players, HHI would be 0.04. In a monopoly, it's 1.0. The US Department of Justice considers any market above 0.25 to be highly concentrated.
More Concentrated Than Telecoms
The US wireless market — often cited as an oligopoly with three dominant carriers — has an HHI of 0.26. The detected web, at 0.56, is more than twice as concentrated. WordPress alone has a larger market share in web frameworks than AT&T, Verizon, and T-Mobile have in wireless, combined.
Why This Matters
Monocultures are fragile. In agriculture, a single pest can destroy an entire crop when every field grows the same variety. In software, a single vulnerability can compromise millions of sites when they all run the same framework. WordPress's 18,005 CVEs aren't just a WordPress problem — at 74.3% detection share, they're an internet infrastructure problem.
