I can add anecdata for the factory profile being very over-red - it's quite obvious out of the box. Not as bad as many Samsung OLED phones you see in stores (typically set to some crazy "enhanced" mode), but it's certainly closer to them than a calibrated screen.

One thing that has bugged me for a while though: why isn't it possible to make my own color profile by hand? Everything seems to imply that you can only get a profile definition file from a calibration device, and I don't have one... but I can eyeball it significantly better than the default profile. Is there something software out there that will let me adjust my curves, like the OS already does with night-mode color balance changes?

I too would be interested in such a tool. I've had some luck finding close-enough ICC profiles, but it would be great to dial it in.