This article is a very good analysis in general although this particular conclusion seems to be an overstatement in my opinion. Most people I know in Russia can see a causal connection between Putin's politics and the economic situation.
This is indeed a very valid point in general. I just don't think it specifically applies to modern Russia for two reasons:
1) especially the older generation in Eastern Europe has a strong tendency to blame everyone else ("them") for any failures; the attitude is sometimes called Homo sovieticus (after Mikhail Heller's book) or "sovok" in Russian
2) the whole point of Putin's "raising Russia from its knees" movement was about the state taking more responsibility