You have to admit that's actually a pretty decent scenario, if Brady was comfortable with the idea. He gets to enjoy life and time with his family as the undisputed GOAT with enough hardware to break any mantle under the sheer weight of it, and we move forward with a young quarterback that quite frankly is starting his career in a better position than TB12 himself ever had, has had a chance to learn and home his game for years understudying behind the best quarterback there ever was, learning the ins and outs of the game from the best coach there ever was, and has an excellent roster around him.
The deck is stacked in Garoppolo's favor if he takes over in New England within the next 2 years. Jimmy G is already generally accepted to be an above average quarterback and has room to grow. We could, theoretically, just keep winning Superbowls much to the disgust of the rest of the league with a young quarterback who could be at that level for another decade. We wouldn't have the GOAT anymore, and I'm positive there would be moments where Garoppolo chooses a bad moment to be young and we lose a critical play Brady might have gotten us, but in theory, Garoppolo could be a Steve Young to Brady's Joe Montana an we just keep going at a relatively high level for several more seasons, maybe even another decade and a half, which Brady wouldn't give us.
That's the sunny-side-up version of the Garoppolo succession scenario and frankly my opinion is that that's a pretty rosy scenario.