Player development is non-linear, even more so for Catchers.
Danny Jansen is a pretty good example. He was an offense-oriented prospect, couldn't hit for s*** when called up to the bigs but was a defensive stud, and has now settled into a pretty solid power-hitting Catcher with good but not great defense.
Heck, even veterans experience a ton of variance year to year. JT Realmuto seems to alternate between a 128 wRC+ bat or a 107 wRC+ bat each year.