I work in a very relevant industry and I have no clue where has this come from.
I strongly believe that nothing of this sort is gonna happen. May be just commercial vehicles would be converted to CNG like in Delhi, which would be good thing.
Interesting thing is that the organisation (I think the association of auto drivers) that filed the Public Interest Litigation petition in the court did not request for any such order. They just asked for the CNG rates in Gujrat to be equal to those in Delhi/Mumbai.