Was the shirt worn by Freddie Kitchens a big deal? No, not really. Did it motivate the Steelers as they prepared for the rematch with the Cleveland Browns? No, probably not. Should Kitchens have worn it? No, he shouldn't have.
All those statements can be true. As a head coach of an NFL team, wearing something such as a 'Pittsburgh started it' t-shirt isn't the best move. Sure, everyone will shrug off the 'it's a bad look' cliche but there's a lot of truth to that.
A coach is supposed to set the tone for a team and when he does something that takes all the attention off the team and their performance, it's just unnecessary.