This is a great point.
By and large the patriots have tended to devote few resources (picks, cap space) to surrounding Brady with weapons. The obvious reason being that Brady is so good he gives you an elite offense by elevating decent weapons, so let's devote more resources to the positions Brady cannot impact, such as defense.
So to argue Brady's value should be diminished because of the defenses on his team is wrong. The patriots were able to use high picks and big cap space on defense BECAUSE OF BRADY. Had Manning or Rodgers been as able to be so great without being surrounded by exceptional skill
position players, there teams could have invested in defense.
Since Brady has become QB the patriots have had 14 first round picks. They have also had 4 years without a #1 so I will consider the first choice that year to be "their 1".
13 of the 18 were defensive players.
2 were OL
2 were TE
1 was a RB
The TE and RB were in 2002,2004,and 2006.
The patriots have not drafted a skill position player in round 1, or with their first pick since 2006, and in those 11 years the only first pick on the offensive did of the ball was nate solder.
So please try to use the defense against Brady because he himself is the primary reason they are able to built a good defense.