Russia hasn't been good enough to compete for an Olympic medal since 1998, when
the last of the Soviet-era kids were still in their prime. The fact that Canadians still obsess on Russia as being their only real rival is testament to the impact that the Soviets made in the 70's and 80's.
And yes, motivation was a huge problem for Russia in Sochi. The Russians played a very spirited game against the United States, but the US is considered by Russians to be their main rival. Stop accepting the pre-packaged, lazy pablum that NA announcers feed you about the Russians (e.g., "the Russians are going to be really pumped to play in Russia"), because the so-called passion and hunger for a medal was never really there.
Of course, of equal importance was the fact that Russia didn't really have a good enough team to compete for a medal there. However, I would say that Russia would have quite likely been highly motivated to play Canada, because Canada was favored by everyone to win. Since anything can happen when emotion and passion is there, Canada may have caught a break by not having been scheduled to play Russia.
There is no rivalry at all for Russia with Finland, Slovakia, Slovenia and Norway, and in all of those games, Russia showed no intensity at all. Finland is very good at executing its defense-only strategy, but its really hard to get motivated to play the Finns when they just trap, trap, trap to slow the game down to a halt. The introduction of junior leagues and expanded pro leagues in Russia should help down the road, but for now, I'm the first to admit that Russia just isn't very good.