There are basically two forms of Russian apologist. The first is the most obvious: the Russian trolls who churn out the standard Kremlin narrative. For the most part, these are merely tedious and a waste of space. The second, however, is the kind of person termed "a useful idiot" - the sort of person who in the 1930s wrote loving articles about Stalin while that psychopath was busy slaughtering and imprisoning millions of hapless captive citizens.

This kind of person - the apologist for brutality - is psychologically unable to deal with harsh reality. They need some compensation mechanism by means of which to push reality away. The easiest is to identify with the aggressor (a version of the Stockholm Syndrome) so as to imagine that they themselves would remain safe even if the aggressor were to reach them personally. It's a sad and indeed rather pathetic psychological defense mechanism, and it leads to a great deal of nonsense being spewed out, but as long as humans are emotionally dysfunctional we will always have those who seek to praise the powerful while blaming the weak.