I mean, we can certainly waste a lot of time cherry-picking stats. While we gave up less passing TDs under Richard, the passing defense also increased in total passing yards allowed, yards per attempt, and opponent's completion percentage.
I think my larger point is simply that when Aaron Glenn began his tenure here, he inherited a pass defense that was perennially either #31 or #32 in the league. And under his tutelage it became one of the better units in the league (ranked #5 when he left). Richard seems to have picked up right where he left off.
But this revisionist assumption that Glenn did a poor job here (which was the origin of this discussion) is completely baseless and flatly incorrect.