I've addressed this repeatedly, going back to when he was hired. Actual goal production with Tortorella is more instructive than xGF because his play style ticks up that stat, but does so by pounding easy saves at goalies because his restrictions on playmaking means the goalie is usually set. This is why over a massive timespan, Tortorella's teams have GF numbers that clearly (and sometimes massively )underperform their xGF, which shouldn't be the case. Those two stats should begin to line up over enough time.
You're leaving out the vital context that not all shots and chances are equal, that the things which happen prior to a shot matters, and that Tortorella preaches a play style that neuters threat from their chances.
Are you omitting important information deliberately to be dishonest in support of your default devotion to authority, or do you just not understand this stuff? It is one of the two things.
And on top of that, their suite of defensive metrics aren't hot either. Not bad, but not good and definitely not great. Just adequate. So even with good goaltending, they were going anywhere. They'd have needed "steals games" levels of goaltending to get anywhere.
Things flat-out are not as rosy and nice as you claim. The eye test at the time showed that, and the metrics (the whole picture with proper context, not your selection of only the bits you like) also show that.
