With the expansion of NFL practice squads that started as a necessity during the 2020 covid season, teams have more leniency to stash away veteran players. This was a significant change as it allows for stashing players that can help your team this season, rather than the practice squad being mostly a developmental group as it was in the past. The Steelers have greatly benefited from this in a season where attrition on defense has become an increasingly large issue.
Head coach Mike Tomlin has talked about this at multiple points throughout the season. First for guys like ILB Mykal Walker who had over 100 tackles with the Atlanta Falcons a season ago.