The difference is in the offense. 120 offensive rating last year, just a 109 this year. It's easy to look at Clarkson and there's some truth to that, but he hasn't been as far off of last year as you would think. In this lineup last year, he had a 52% TS. This year it's 49% which is obviously worse, but not exactly something that would drop the lineup. The difference between Niang and Paschall comes at smaller volume of shots, but Niang was 60% TS compared to just 30% TS for Paschall. So yeah...big difference there. But at the same time, Joe is really propping up this unit with his shooting. He's at a ridiculous 91% TS which is really. Mike has also been shooting above his head in this unit so I don't think the shooting as a unit is where we can't point the blame. Clarkson and Paschall are shooting worse and will get better, Ingles and Conley will come back to earth.
Under further inspection, the real culprit is that this unit is turning over the ball like crazy. Last year the lineup turned the ball over 12.4 times per 100 possessions. This year it's 19 times per 100 possessions! That right there is making up most of the difference in offense. Gobert is the biggest difference here. Last year at 2.7 turnover per 100. This year 7.2 which is absolutely crazy. His offensive fouls have gone up from 0.16 to 3.27....which seems unbelievable.
On paper, the problem is turnovers and not poor shooting. I don't know how turnover variance compares to shooting variance, but I suspect that will normalize down the line. Maybe you can point to Paschall hurting the spacing causing turnovers, but it seems like a reach. Rudy has just been turning the ball over like crazy.
The other thing that has gone wrong is when Conley or Ingles have been out. Last year Oni stepped in and those lineups were even better. It's the main reason why I think he should still be on this team. This year, the combination of Oni/Butler/Forrest has not gone well. Last year we were +31 when Oni came in for one of those two. This year, we are -31.6 when one of those three have come in.