The context here is that the previous policy, the EV availability standard, specified a market share of sales of specifically EVs, battery electric vehicles and plug-in hybrids that would increase over time. The shift to a GHG standard responds to requests for more flexibility in achieving emissions reductions.
In the near term, that opens the door to non-plug-in hybrid vehicles that are still powered by fossil fuels but that offer significant reductions in overall fuel consumption. That policy does create flexibility. The only question is, in the long term, how stringent do the targets become? After a certain point, you need to shift towards plug-in vehicles to attain more significant emissions reductions.