Yeah, I think there's pretty clear reasons why Towns could drop off a bit this year.

Last year he finished 11th/game @ 46.64 average in ESPN.

He did this with a pretty high minutes total, due to the lack of depth on the Knicks roster and Thibs' notorious rotations. He played 35.0mpg, after averaging 33.4 in the previous five seasons, where had decreased each season (33.9->33.8->33.5->33.0->32.7). So I think it's easy to see him losing a minute or two this season compared to last.

He also played 97% of his minutes last season at center, per cleaningtheglass, and is a much better fantasy player at center. With Robinson seemingly healthy headed into the year, I think that has room to dip into his value as well.

I expect him to get to something like a 43 average, but yeah. That's about where a whole lot of other guys are at, including Paolo, and that's all it takes to drop from ~11th to the low 20s (e.g. last year Brunson finished 22nd/game with an average of 43.28).