Who knows if it's true. I don't think Lee's play is a problem - he's our best defensive perimeter player, and OK on the offense, save the low 3 pt percentage.
Bigger issue is the surplus of guys who can play 1 and 2: Rondo, Terry, Barbosa, Bradley, Lee, and even Paul when Green goes to 3. So the brass might be looking for a way to parlay some of that excess into a guy who can help with the interior D.