I would not fire him. He gets his team to the playoffs every season, and the playoffs are often a crapshoot. For example, is Mike Zimmer a better head coach if his kicker makes a 27 yard FG? For some blind fans, he would be because playoff W-L is the be-all, end-all. Lewis is a good coach in a league full of mediocre ones. His players have often not stepped up in big games. He's also had some bad luck (Dalton injury, players losing their cool, etc.).
Wait a second..his players have not stepped up in big games? so that's on him IMO To Coach= to inspire, motivate, direct (my interpretation) You need a playoff big game criteria as a measuring stick...because just winning and even winning well in regular season ain't enough. Close but no cigar, sorry to say...If you are Zimmer yeah you put that on your resume I got them this far till Adrian P fumbled and kicker bumbled. So the end up is the Coach looks ok but fans and owners get no SB. Another year maybe grabbing for prize...The Prize separates the Great from the Good Coaches in NFL imho Even Bowles got that right saying season not success without a Championship
From the perspective that Lewis has always underachieved year over year given the level of talent he has had, yes he should be fired. The problem is, that talent level still exists (for at least another 2-3 years), so making a change now would require bringing in someone who could harness that talent and produce results in that short window. Now, if there were a candidate freely available, you could try to pursue him then let Lewis go once you've locked him up. There does not seem to be a good free candidate available. Payton and Coughlin would be the best candidates for this team, but they are both contractually bound, meaning they'd have to ask permission to speak to them, something you really don't want to do while you still have a coach. Maybe Saban would be worth recruiting from the college ranks, but aside from that, Cincy can only hope Lewis eventually slips and falls into a pile of luck like Cowher eventually did after years of disappointments.