Russia’s President Putin says the Soviet Union’s collapse was “the greatest geopolitical catastrophe of the century”.
Why would I give two cents for your opinion when I’ve got the man’s own words?
When was it said?
What specifically was he addressing, to whom?
Was he talking about the system, or the concept of a vast Russian empire?
Since he is now acting in a manner which is consistent with Russian, rather than Marxist, interests, the rational conclusion would be that it is the empire he was regretting not Communism.
Since your basis is quoting the man out of context; you have no real basis.