This is what we call "Damage Control". He, along with the rest of the Steelers star core, is a diva. After watching year after year of this core this is the only conclusion I can come to. Tomlin has no control of this team and the inmates are running the asylum.
Ben - throws everyone under the bus, takes credit for successes, skirts blame for failures. Threatens to retire every season so that he gets his way, but then complains when the Steelers draft a potential replacement.
Brown - Doesn't get the ball enough so he goes on the sidelines and cries about it. Getting in the face of the QB coach on the sidelines. Now he's not showing up to teem meetings for "personal matters" the day after throwing a tantrum on the sideline. Tomlin wouldn't confirm that the absence was excused, and knowing him he would have squashed it quickly if the team was fine with it. Judging by his remark about looking forward to meeting with AB, he clearly didn't speak to AB about it first.
Bell - Do I even need to explain? Guy can't even play a whole season, suspended multiple times, injured multiple times, but he wants to biggest RB contract in NFL history. He's now taken to trolling his team on Twitter/Instagram. First by posting an 'inquisitive' emoji after the Steelers tie (read:loss) to Cleveland and now by liking posts about them losing to KC. On top of that, he's been working more on his rap career than his football career.
Bryant - Albeit, he's gone now, he was developing the Diva attitude under the tutelage of Bell, Brown, and Ben. He saw how the team was run and fell into line with it. The Steelers bent over backward to take care of Martavis Bryant and he repaid them by demanding a trade and promptly getting himself suspended long-term AGAIN.