Adobe's raw conversion on the 3100 files that are 16 bit IMO has always been lacking. If the image is needing any push in shadows, you get a red tint to the file. I have opened several issues with them over the years, but have given up. Adobe tends to be a one and done on many cameras.
I agree their current Flat Field needs to be updated as it's based on results from the IQ180 80MP back, and never has been adjusted for the CMOS backs, which have quite a bit of color cast, besides the IQ4, which seems to have resolved that issue based on the images I have seen.
Paul C