Basketball-reference predicting regression for Milwaukee Bucks’ starters?

Basketball-reference predicting Milwaukee Bucks’ regression: Grayson Allen

Grayson Allen started the most games at shooting guard for the Milwaukee Bucks last season, and I am operating under the assumption that will be the case this upcoming season as well until seen otherwise. Wesley Matthews is an option but given the fact that the Bucks are stocking up on veterans, it seems that they’re trying to keep the older players better rested for the postseason.

Grayson Allen outside of some hip injury issues had a pretty good regular season for the Bucks in 2021-22. Looking at his per 36 minute statistics is encouraging given he was usually the fifth option on the team after the big three and Bobby Portis, per 36 minutes Grayson averaged 14.6 points, 4.4 rebounds, 2.0 assists, 0.9 steals, 0.4 blocks, 0.9 turnovers and 1.9 fouls. Allen shot 44.8 percent on field goals, a career high 40.9 percent on 3-pointers and 86.5 percent from the free throw line.

Grayson Allen will turn 27 just before the start of the season, he is in his prime, so a regression on anything shouldn’t be based on his age and given the stars that he plays alongside it is not likely that he will be facing any extra defensive attention. Even still basketball reference has predicted the following per 36 minutes stats: 15.0 points, 4.6 rebounds, 2.4 assists, 1.0 steals, 0.3 blocks, 1.1 turnovers and 2.0 fouls on a predicted 44.5 percent field goal shooting, 40.4 percent 3-point percentage and 85.7 percent from the free throw line.

So a predicted slight uptick (0.4 in points and assists, 0.2 in rebounds) on predicted lower percentages, why the predicted slip in efficiency for a player who conceivably based on his age, role with the Bucks and second year in a system he joined last season? This prediction is almost harder to understand than Jrue Holiday.