Such a sad event in any case.
The problem that Russian aviation faces now is a huge shortage of pilots. This leads to poorly trained pilots (that may get away with poor flying skills in an Airbus/Boeing) who are flying Russian aircraft which demand much more.
I believe the last TU-134 that crashed was because the pilot was a retrained helicopter pilot who has not developed instrument flying skills.
The country has 2 flight schools in which the students may flying 150 hours over the course of several years and the amount of pilots retiring exceeds the number replacing them.