All forms of wear and tear count. Wright's knee was surgically repaired last year. As we found out this year with Eddie, knees matter.
If he's in the bullpen, I think it makes sense to use him in inning-plus relief, but I think it's going to be more important to have Wright ready to go in the Bronson Arroyo role, able to come in and replace a starter at a moment's notice, than it is to try to abuse his mystical knuckleball powers over the course of a series.
Besides, Wright is not one of my top 3 relief options, those honors go to Kimbrel, Brazier and Workman. Workman can go 1+ innings but has also evolved into the guy you bring in to strand baserunners, and he's been very good at it this year. Workman to finish the inning and maybe pitch another one, then turn a clean inning over to Wright or Velazquez, sounds like a strategy that works.
As for bringing Wright into high leverage innings... eh. He's good, but the knuckleball can be a very inconsistent pitch to rely on in high leverage situations so I'd rather keep Wright in reserve than try to plot out a baseball playoff series as if it was a dance routine..