I bet if we asked Montez, he'd be the first to say that @Wazzu was the worst game he has ever played in his life and that while there may be reasons with the conditions (and Lindgren doing a horrible job game planning for those conditions), those are only reasons that a QB wouldn't put up great numbers that night... not an excuse for how he performed.
But I don't think it's fair to judge Montez so much on one game. I also think that his receivers let him down a ton in 2017 with dropped passes, not fighting to get open and not blocking for each other at anywhere near the level they'd done that in 2016.
Early in the season, Montez was giving up on his pocket too early and it was throwing off the timing of the offense with the receivers. He seemed to largely fix that.
But he also seemed to get too careful at times and ended up aiming the ball, losing his accuracy on what are easy throws for him.
Also, inexplicably, it took a long time before he found his stroke on deep passes. I think there were some footwork issues mixed in there that contributed.
Bottom line, though, is that the size, arm strength and scrambling ability is an elite package for a QB. It's all there for him to be a special player this year.