Derek Carr - Why People Dislike Him (IMO)

Elvis said
Without even digging deep at all. Brady has been good everywhere and with anyone. Everyone who has had to perform without him has been awful.

Rouxble said
Peyton Manning is another QB who was good everywhere and with anyone, and his coaches didn't find nearly the success without him as they did with him.

There are a lot of things that are missed with these 2 examples. Both Brady and Manning only ran 1 offense their entire career and by definition, both were "system QBs." When Manning went to Denver, the Broncos ran the same offense that he ran in Indy. When Tom Brady went to Tampa, he could not effectively run Bruce Arians offense, during the bye, elements of the NE system was implemented and by the next season, the offense looked nothing like a Bruce Arians offense.

Tom Brady 12 games before bye: 275ypg on 64% completion. 28TDs/11 INTs 95.1 passer rating
Tom Brady 4 games after bye: 333ypg on 69% completion, 12TDs/1 INT, 126.9 passer rating (having AB, who was familiar with NE's system didn't hurt)

Tom Brady:
Under Bill Belichick, New England has always ran a variant of the E-P system that Charlie Weis implemented. When Charlie Weis left to coach Notre Dame, Josh McDaniel's kept the same offense in place, as that was the only system that Tom Brady knew. By time McDaniels left, Brady was in that system 9 seasons and he mastered it. Fun fact, Mac Jones ran that offense and they made the playoffs. Too bad the league cracked down on bringing in cameras to practice.

Peyton Manning:
Jim Mora brought in Tom Moore as the Colts OC. When Tony Dungy became coach, he retained Tom Moore and Manning continued to run the same offense. The difference maker that is ignored is Jim Caldwell being his QB coach. One season with Jim Caldwell and he got his first MVP but the system never changed.

Rouxble said
You can take any good offensive coach and look at the QB's they've coached, and you'll find that they have tremendously different performances depending on who is under center. They are masters of tailoring the offense to their QB, but can't seem to figure it out when they don't have their guy. Here are some QB ratings of note, only going with QB's that have started at least one game under these coaches:

Reid with Mahomes, Smith, Vick, and McNabb - 93.5
Reid with anyone else - 74.6

Shanahan with Purdy or Garoppolo - 102.8
Shanahan with anyone else - 82.9

McDaniel with Tua - 105.1
McDaniel with anyone else - 72.2

Payton with Brees - 101.5
Payton with any other Saint - 89.3 (worth noting he had Winston at a 101.5)

When you take this at face value, this is telling me that all of these coaches were/are able to produce with the QB that they named the starter. We could technically add another line for Lance since Shanny named his a starter at the beginning of the season and we can also do the same for Winston, since he was named starter.