There's a lot of love for Espinosa's defense buried in those stats, along with his nice offensive recovery. While his arm has been scattershot at SS (5 throwing errors), he has been remarkable good at getting to balls within the normal SS range, and has been able to get to balls out of zone at a very high rate. UZR of course loves him, too.
If we ever bit the bullet and used him in a deal for a white whale, most teams would look at him as a SS. If Rendon were capable of playing 2d, this might be very tempting.