Yes, McCabe is a real thing. I haven't really found it that useful myself -- I'm not sure that you can adequately measure something fuzzy like "complexity" through static control flow analysis -- but sure, I'm willing to accept that it could be useful in certain circumstances.
What I am saying is that this guy is cherry-picking a specific metric (out of many that he could choose) that makes his tool looks good. I could just as easily come up with a metric that sorts Django to the top of an arbitrary list. That wouldn't be useful, either.