Downshift on icy road?

I think a moderate amount of engine drag is the way to go. Just enough to keep road speed from increasing rapidly.
Downshifting but not over say, 2000rpm.
Traction control may help by applying brakes to individual wheels while the driver has no foot on gas or brakes, IDKFS.
While ABS has the advantage of controlling individual wheels its application is rather abrupt, which isn’t ideal in ice and snow.