Based on wRC+ and OPS+, Russell has never been an average MLB hitter. Even in 2016--his best year--he was about 5% below league average. Obviously, that's fine for a great defensive shortstop.
In 2017, his wRC+ was 85 and his OPS+ was 84. In 2018, his wRC+ was 80 and his OPS+ was 74. He has been a bad hitter the last two years.
Since Russell came into the league, his wRC+ is 88. Across Chicago, Tim Anderson came into the league a year later...has career wRC+ is 86. Russell has really just been a better fielding version of Tim Anderson.