The new gear shifter driving ring is dark grey and not red. The colour of this piece is selected freely, as it does not look like anything else. But it makes sense to change the colour from the old red version, as they can't replace each other in a build. And I think a neutral colour like dark grey fit a driving ring better than e.g. an orange or green one.
Red is also used on the new gear wheel, to not confuse it with the old dark grey one, and fit the colour of the 8 teeth sliding wheel.