Just kidding. He doesn't say that.
You should probably read the first two paragraphs again and take into account that help defense is hardly even mentioned in the article. He mentioned one metric, which while it shows something of value, does not tell the whole story. Millsap is the 8th worst defender in the entire NBA? Come on.
Well, that's what the stats say. How would you argue otherwise? Also team defense starts with individual defense. If one guy slacks, the other team will go that way and then the entire defense has to adjust to cover for the weak defender. Did the Jazz give up any open 3s this year because the wings were collapsing to cover for the weak interior D? Just wondering.