I think for the postseason especially, bullpen arms are more important.
You need 4 starters max in the playoffs. If healthy, Skubal, Flaherty (I’m assuming he figures things out) Mize, and Olsen are capable enough, and at there best match up well against most. If one starter has a short outing, if you have enough solid bullpen arms you’re ok as the days off means guys can go almost every day.