The optimistic take is that Mac proved last year that he can be the game manager, Captain Checkdown type quarterback; but he was criticized a lot last year for leaving a lot of opportunities on the table, not taking enough shots down the field. Now he's doing that, hopefully at the urging of his coaches, and there's some predictable growing pains. Maybe he can figure out how to balance risk/reward, and minimize the turnovers; maybe he can't, and the coaching staff will have to stress ball security at the expense of those downfield throws because Mac just can't process enough information post-snap to make the right decision.
To draw a tortured analogy, it's a little bit like Jayson Tatum and Jaylen Brown trying to figure out who they can be as playmakers last season. Sure, there's a ton of turnovers, but it's a growth process that's going to have to happen if the team wants to realize its full potential.
The issues that we saw last week from Mac are at least theoretically correctable, even if you're not optimistic he can actually do so. I've been down on Mac, but I have to admit I was encouraged by the way the offense moved the ball and some of the intermediate throws Mac made last week.