Coaching definitely has to improve. It seems like everyone is still stuck in 1985 with their tactics and while it works internally, the teams consistently fail when they hit the international stage.
This does not explain all. Russian hockey has declined from what it was in 1985 but it has also declined from what it was in 2000-2005.
The level of import players is total crap, though with a few exceptions.
Vasicek, Dallman, Kapanen, Aaltonen, Kontiola, Demitra, Hartigan, Weinhandl, Mårtensson, Niskala, Rachunek, Sykora, Platt, Persson, Cajanek, Immonen, Fransson, Stumpel, Petrasek, Podhradsky, Radivojevic, Ruzicka, Baranka, Fernholm, Jagr, Cervenka, Rämö, Kukkonen, Marek, Rolinek, Lehterä, Komarov etc are not crap. This is by far the best crop of imports in any European league.
Take them away and what do you have left?