It's a risk reward proposition. Their RZ offense is even more conservative than the rest of their approach right now. Every team knows they're going to run on first down, shotgun alignment WR/TE screen on second down, and then (usually) hold the ball waiting for someone to get a three step separation (which rarely happens in the RZ) or RB check down on third down.
The entire approach is about protecting the ball (at least to me) with the least risky throws in football. Is that Mac's early season recklessness? Likely some. Is it Patricia's "engineer mindset" (love that BTW whoever coined it) which values safety over risk? Likely some. Is it the unsettled and poorly executing OL? Likely some as well. Is it BB not wanting to further damage his QB's confidence by putting him in risky situations where failure and success are not as balanced? Also probable.
Winning against teams that are more talented is probably not going to happen without taking some risks. Can they explode in the Patriots' face? Absolutely - we've already seen the terribly timed pick-6s from riskier throws, but we also have seen zero reward recently as well with production in the red zone an all time low for the Pats.
The Vikes won in large part due to trust and risk - Jefferson was well covered and even double covered on some throws. The odds weren't in the offenses favor, but they threw it anyway and the kid made the plays.
I'm not saying chuck it up for grabs (which is what the first four games of the year were...back foot desperation heaves to no one in many cases), but sometimes for this team to take the next step they will have to throw it to the guy that's covered and trust him to win the matchup. (I dunno...maybe not Parker or Agholor....on second thought it was their non-wins that led to some of those early year INTs...maybe Meyers, Rham, and Henry?)