Sorry, but the whole thing was couched on “How Sam feels about this”.
Demon!Dean was about how Sam missed his nanny!Brother, always at his beck and call.
MoC!Dean was about how far Sam would go to get the Mark off Dean, and we never got to SEE Dean Lose control so badly that it merited Sam’s Chicken Little Attitude.
Darkness!BondDEan was about getting Dean out of the major decisions because “he couldn’t kill her”, and at the end, it was solved by shoving him aside since Amara found her love for humanity out of a conversation with a random woman in the park.
NOTHING in seasons 9-11 was about Dean.