Sure the level of hockey collapsed after 1991, no one has tried to deny this.
I'll try. While I don't doubt the resources aren't the same as they were under the communist system, the main reason for Russia's lack of success internationally over the last two decades is it's now in the same boat as everyone else and most of its officials and fans are in denial.
The massive advantages they had heading into international play in the past -- the discriminatory IIHF ban against North American pros, the Red Army hothouse system that put almost all of Russia's top players on one team to develop together for years, and not having to throw together ill-prepared teams at the last minute -- no longer exist.
If that's what you mean by collapse, I guess I agree with you. Otherwise, no.
The fact that a bunch of U.S. university players were forced to go up against the Soviets in 1980 says everything that needs to said about the undeniable and unfair advantage Russians and others had over North American teams for decades.
The Russian hockey system was geared toward winning internationally and everything was poured into that to the exclusion of all else. Now that's no longer possible and you're seeng the result. The myth of Soviet supremacy was built on an ice surface far more tilted than anything you claim with the Canada Cup.