The Rangers are a playoff team even if Shesty regresses a little, let's take off the homer glasses here. Are they a Conference Final team? Probably not.
They were middle of the pack/bottom third of the league in most major underlying metrics last year. They struggled 5 on 5 and gave up high quality chances. At the end of the day, basically everything was just pointing to: Shesterkin = very good.
Yes, they probably make the playoffs, but the team itself was a statistical anomaly last season.