While that trade was certainly huge for them, Forsberg was really the only piece of it that had a major impact on their Cup wins. They still don't win the cup without Sakic. They still might not win the cup without the Roy trade.
Roy is the biggest reason the Avs won two cups. People link the Roy acquisition to Lindros because Thibault was used to acquire him from Montreal. There were still a ton of things outside of that trade that had to happen for them to become a winner.
Let's also not forget that the 96 final may have been the most lopsided finals in the modern history of the league. Florida was carried by Vanbiesbrouck for the first three rounds. By the time they got to the finals, he was gassed and they were quickly swept, with only game four even being close. The Avs likely don't win that first cup if they go up against the Pens who were absolutely loaded with a prime-aged and healthy Mario, Francis, Jagr, Nedved, etc.