There is no way Mtl looks at Trouba.
He wants to play right. Habs have the newly acquired Weber and Petry who has a full NMC at right.
Who are they going to move out for Trouba?
I think it would be beyond silly to simply not look at a player with the potential that Trouba has just because we have two other contributors on the right. I don't think too highly of Bergevin but I suspect he feels the same way because there are no other 22 year old NHL veteran defensemen, with top pairing potential, who are ever available on the market.
If you can find value in the market, the trigger needs to be pulled and the roster adjusted accordingly. You are selling the organization short as a GM by passing up on elite talents just because your roster (who missed the playoffs and were borderline lottery bound last year) is presumptuously 'set' on the right.
This scenario also presumes that injuries don't happen in hockey, when in reality one of Weber or Petry (who missed 30 games last year) could full well have any number of things happen to them and miss significant time. I never understand the arg. that x team is too deep to add a sublime talent. If a player is better than 50+% of your roster, you should probably consider the value his presence brings to the table
Anyway..
As I mentioned, I don't see us being good trading partners and, as you have implied, this scenario is unfortunately a pipe dream at the best of times for us Habs fans