I think the turnovers are a case of the eye vs. stats.
They might not turn the ball over all that much, but the turnovers they do make are REALLY ugly so they have a tendency to stand out.
Yeah Paul's always been somewhat turnover prone, but having him handle so much near halfcourt means he's getting more of the "Oh my what are you doing" ones.
I think one needs to say 'compared to ______' with that.
Pierce' TO rates are not really high when you compare him to other full time primary scoring small forwards. Especially when you factor in his assist rates (not all small forwards handle the ball near as much).
Among Small Forwards who have played at least 30 games and at least 20 mpg, the league average TOR is 10.14 (hoopdata.com). Pierce' TOR is barely above that at 11.10 and is right in the middle of the rankings. Notably of all such players ranked with a lower TOR rate than Pierce, only two have as high of an Assist Rate (Lebron and Chandler Parsons) as Pierce. Most have a much, much lower assist rate. The average assist rate for this group of players is 14.48 while Pierce' is 18.77.
Of the 5 fulltime SFs who have higher assist rates than Pierce, 3 have higher TO rates than he does. And Parsons, at 10.85 is essentially identical. Lebron is the only one with a notably low TOR -- just 9.32. But Lebron almost NEVER gets called for either traveling or charging - both of which count as TOs, so I don't know how valid we can consider that stat for him.
So Pierce' TO rate is not at all unreasonable when compared to his peers in the NBA this season. It also is basically about the same as it has been for himself over the course of his HoF career.
His TO rates only look high compared to other Celtics who, of course, don't handle it near as much.