Taron Johnson isn't the player he used to be. The Bills need to replace him next year, or play 3 linebackers more and put him on the field a lot less.
Lewis is a depth player and always has been. He is great for what he is. He can fill in at a lot of spots, but he is never going to be a starting caliber player, and that's fine. He is valuable as a depth player, and he usually plays quite well when he plays. But yeah, he'll give up some plays as well, because he isn't a starting caliber player.