Decision making also means making quick decisions whether to run, pass, or scramble, how long to wait for the primary receiver to get separation, and when to kill a play that isn't working rather than force a play and risk a turnover. I get what you're saying about impatient fans, but as mentioned Scott Frost and Adrian Martinez himself acknowledged that Adrian lost some of his confidence last year, and it appeared to be bleeding into his Junior season.
If you want to look at it critically, Frost essentially platooned both quarterbacks to start the season. Both were good runners -- but McCaffrey was a little better. Both were inconsistent passers, but Adrian was a little more consistent. In Frost's tempo offense, McCaffrey was a little quicker getting the team to the line and executing the bread & butter plays --- that's from Frost himself, not armchair Husker fans Given the chance to start against Penn State, McCaffrey played well enough to win the game, a performance pretty similar to a Martinez performance. Both QBs often missed seeing wide open receivers, and neither did a good job of getting the WRs involved.
McCaffrey then had a meltdown performance against Illinois -- Martinez has had those, too --- at which point Frost turned to back to his Junior QB over his Freshman QB. Martinez responded with a good statistical game against Iowa, but a costly turnover. Then followed it up with a highly efficient game against a pretty bad Purdue team. But his confidence is back and that could make a big difference going forward. Not sure why you're quick to dismiss the mental game, or simply throw the receivers under the bus. .
Except for the predictable one series package Frost gave McCaffrey against Purdue, McCaffrey has run the same offense as Martinez. The QB draw is a designed play for both QBs, but McCaffrey runs it slightly better, so he runs it more often. Luke has only 22 fewer pass attempts than Martinez. That's not a wildcat.
The difference between Martinez and McCaffrey isn't night and day. It's more dawn and day. As mentioned previously, we can congratulate Adrian without s#!tting on Luke quite so much.