The NHL is a copycat league when a team employs a successful method or philosophy, others follow suit. The Edmonton Oilers made it common practice to tank in hopes of winning the draft lottery when the NHL switched systems. The NHL now is actively trying to combat the problem of tanking because of how many teams have turned to it.
The Rangers were certainly guilty of tanking down the stretch. They did not rest healthy players, but the team did keep Alain Vigneault as head coach. Typically, when a team fires a head coach midseason if spurs a quick turnaround.