I'm a little late to the Helleybuck conversation, but I'm not sure anyone should discount his performance at all even given how bad the Jets were in that series. Yes, he had the highest xG against total in this playoff round with 19.02 over 5g, ahead of Vasilevsky's 17.29 in 5 and Talbot's 16.2 in 3, but he was also just bad. He gave up 24 goals on those numbers while Talbot and Vasi gave up 16.
-5.0 goals saved above expected total, by far the worst in the round. -1.090 GSAA per 60, more than twice as bad as any goalie who started more than 1 game. The Canucks third string keeper outplayed him by almost a goal per game.
Sure, his team didn't do him any favors, but even the stats adjusted for the quality of scoring chances still placed him as responsible for an entire extra goal given up every game. Any team in the NHL would struggle with that in net, and probably doesn't help the play in front of him if his team loses confidence quickly, even in such a small sample.