Modern defensive statistics are great. And they're sometimes terrible.
Any serious baseball fan will have a hard time completely avoiding modern defensive statistics. If you use any flavor of Wins Above Replacement, you're utilizing modern defensive statistics. Almost every front office uses this kind of data -- I'd say all, but I can't swear every single team does -- so if you're not into the concept, you're missing something crucial about how teams are run in 2019.
By way of SABR's Defensive Index, which combines multiple methods of estimating defensive performance statistically, these stats also play a large part in the Gold Glove awards (7 p.m. ET Sunday on ESPN2).