He listed them as examples of point guards who struggled with their assist-turnover ratio early on but became great PG's in the end. I don't get what the problem is? Never said Russell is the next Nash or Stockton.
We don't even need to go back that far. Stephen Curry averaged over 4 turnovers for the entire playoffs. (4.7 TO during the Finals) Nash had almost 4 turnovers a game during his MVP years. Magic Johnson's career TO average is 3.9.
Turnovers are part of the game if you are a starting point guard. As fans, we over-analyze everything and sometimes focus too much on one stat. You have to look at his overall game and see the adjustments he's making and the teammates that are around him. Also, a lot of the TO's can be caused by bad chemistry as well. Once Russell has a consistent roster around him, the TO's will decrease significantly.