I do think Nagy seems a little out-over-his-skis as a head coach, but it's a myth that his offensive schemes suck. He sucks as a playcaller, but that's a separate issue.
As a designer, Nagy's actually really good at getting receivers open, if you watch the tape. The Bears just haven't had a quarterback who can get the ball to those receivers.
I'm really excited to see what Fields can do when paired with Nagy. I don't think Fields will disappoint. At minimum, I think he's going to be a really good quarterback for a long time.