People, including elites in Putin’s inner circle, perceived as insufficiently loyal to Putin have experienced a rash of widely reported “murder-suicides” of their entire families, and others who have avoided that fate have experienced, other very public, severe adverse consequences.

This, along with Russia’s notoriously pervasive secret police and domestic surveillance may have something to do why even “anonymous” polling of Russia finds fairly small numbers of people willing to say they don't support the regime wholeheartedly, independent of actual sentiment.