2015-16 the team had the worst goaltending in hockey. I discount it from my calculations when it comes to assessing the Trade.
For me, in terms of Subban-Weber, the real comparators are 2015 and 2017. Both teams had Price. And what 2017 showed was that the Trade did not solve any actual problem and did not improve the team at all. With Subban in 2015, the team got to the second round, but struggled to score, and the PP was all too predictable as everything was funnelled to Subban's boomer. In 2017, the team lost in the first round and struggled to score, and the PP was all too predictable as everything was funnelled to Weber's boomer.
Indeed, the 2017 team was much more erratic than the 2015 team, melting down midseason and only righting the ship after firing the coach, only to crap out in round one. So even at the mythical level of 'leadership' the team showed zero improvement. In fact, on balance, it did worse, both in the regular season and playoff.
So Bergevin's big coup accomplished less than nothing. And it's been all downhill since then.
Meanwhile, of course, Nashville has taken a huge step forward. Now people will spring up and say that the trade had nothing to do with that. But all I know is that if the Habs had made the finals and then finished first overall, Bergevin's defenders would be clicking their heels and crediting the trade as a major contributor to that result.
The trade was dumb and Nashville was the big winner. No other way to spin it.