60% is a big number. I'm one that's quick to forgive the GM because I think its a logical fallacy to assume there is always combination of possible moves and decisions that will yield a superbowl every year. The players themselves don't always play up to their potential but I'm quick to forgive them too because unless you think they aren't taking their preparation seriously or get lazy with their body. Would Micah Hyde have caught the ball with an extra hour of jugs machine drills? My feeling is no. Coaches on the other hand are responsible for both the long term philosophies and short term strategies so my thinking would be that if the right combination of decisions lies within just one guy, its got to be them simply by the huge volume of possible decisions they have. Also those decisions are less data-driven than those of a GM so the human element is more pronounced. Just my two cents.
I also don't know that we do such a better job restocking on offense. We're perpetually solid at QB and WR but the line, running backs, and TE positions have all been a roller coaster. Rodgers is a one man offense and McCarthy has shown to be a very competent game planner and play caller. Those two just mask a lot of weaknesses IMO.
On defense we've had an embarrassment of riches at the cornerback position compared to other teams. For the most part we've managed to keep a premiere pass rusher on retainer as well. Capers deserves the criticisms he gets IMO. He does have shitty luck though.