Somehow, I totally missed this important piece of information.
FWIW, I went to the VW website and scanning pages of fluff, never saw RWD mentioned. I went back and read most of the ID.4 posts on here and didn't notice anyone who drove it mentioning the ID.4 is RWD.
That explains the low regen levels and the lack of true One-Pedal. In slick road conditions, too much RWD regen would result in an immediate skid.
Moot for us, as we would only consider the AWD version, which won't be available until late next year.
It also explains why they went with rear drums. The rear braking is already being assisted by the motor. The intended use case of the ID.4 is not on the track, so beefy brakes in the rear aren't needed.