Defense is far from Pop's focal point, which is evident from his excessive small ball lineups when the Spurs clearly don't have the personnel to use it, and his over-usage of guys like Finley and Mason over the last 2 seasons..
The fact that he has used Udoka and Bogans as defensive stoppers the last few years, failing to realize that the league has gotten more athletic(which is needed, especially with the lack of handchecking), also speaks on his loss of defensive recognition IMO..
I'm not a Pop hater, never have been, but I can't see how somebody would say he's still focused on defense..