Goes without saying we need the qualities you mentioned. Are you saying a cup can be won without physicality/hard checking in your game?
Physicality is one of many different attributes that a player can utilize to potentially assist in their offensive or defensive play, but hitting a ton does not itself help you win, and it is not necessary to win a cup. In fact, 12 out of 18 cup-winners in the cap era have ranked in the bottom half of playoff teams in hitting. A cup has not been won by the highest hitting team in the playoffs, but it has been won by the lowest hitting team. The average playoff hits/60 of the cup winners in the cap era is 30.07 hits. Throughout the Matthews era, we have averaged 34.91 hits per 60 in the playoffs. Through the 5 year period where select people loved to complain we were soft, we averaged 33.44 hits per 60 in the playoffs. Both above the average of cup winners.
Physicality has never been our issue in the playoffs. In fact, it has often been detrimental to us, causing major penalties that throw away games, and suspensions - including to significant players - that have potentially cost us series. We focused way too much on "snot" this year, and all it has done is hurt us. We allowed the first goal of the series 2 minutes in, because we chased a bad hit and allowed a 2 on 1. We've thrown away PP chances and put ourselves on PKs we can't kill with constant undisciplined behaviour. We've killed our own momentum, and created chaos that Boston has thrived and scored on. We ignored defensive play and PKing to instead just cram our defense with big hitters galore, and all we did was make them so slow and unskilled that we can't exit our zone or transition.
Hitting can be helpful. Hitting can be fun. But unfortunately, some put it on a pedestal and seem more concerned with the playstyle we lose with, rather than actually being good.