I honestly feel that defense at C can be over valued. Only 12 catchers last season had more than 450 PAs. That means the vast majority of teams are running 2 catchers with a semi equal split of time. As long as one of your catcher is strong I feel it all evens out. Teams don't run like they did in the 80's so if a guy steals a base it sucks but it's hardly the end of the world. Passed balls aren't very common either even with iffy catchers.
Ultimately, to me the most important thing a catcher does is calling the game. Great catchers make their pitchers better. However, that's hardly related to defensive ability. It's 90% preparation and some feel. Framing is probably rightly considered part of that but again, that's something you learn more than a physically ability. Austin Hedges is arguably the best defensive catching prospect right now and in his first call up he's hitting .116/.133/.209 and that's honestly the book on him with a 40 hit and power grade. I'd much rather have someone who's a bat you're not sure where will play than an amazing defensive player who flat out can't hit. Others are welcome to their opinion but all Schwarber has done is rake. He's been over .390 OBP at every stop including a brief stay in the majors. The team is going to find a way to get that into the line up considering all of 7 players last year had a .390 OBP.