Not being a jerk but did you watch the Pats last year? Cam is done, he has nothing left, he can barely throw and the Pats have no upside with him...Rodney Harrison describes it best:
https://www.nbcsports.com/boston/patriots/rodney-harrison-cam-newton-cant-play-football-nfl-anymore
As for Jimmy G I think most Pats fans are realistic...he is an upgrade over Cam first and foremost...with BB and McDaniel and his familiarity with them there is hope he can become an above average starter that you can win with if his surroundings are solid which after the free agency binge is hopefully the case...I don't think anyone expecting him to become an All Pro but outside of getting one of the big time rookies he is the best option they have to upgrade this position at this point and time (and again, they are familiar with him)...my first preference is trading up for one of the big 5 rookies but I am more than fine with adding Jimmy G and than adding one of the second-tier rookie QBs and crossing my fingers that works out short and long term...as long as it is not Cam I will be able to look forward to this season.