Author states "Ontario’s purchase subsidies.... have been shown in a multitude of peer-reviewed environmental studies to be inefficient. They are also regressive, in that they provide the biggest benefits to buyers at the very top of the income distribution". 

 I would like to see these "peer-reviewed environmental studies".  Author provides no references for these or any other statements in his article. 

And how do the EV incentives benefit only top income buyers?  The incentive is available to all EV's such as the Chevy Volt, Bolt, Nissan Leaf., Ford C-Max, which if you account for gasoline savings and incentive, are equivalent to an internal combustion engine car priced between $20K-$30K.
The author's argument that CAFE standards don't accomplish CO2 savings is questionable and does not apply to EV exclusive manufacturers like Tesla.

EV incentives do work - just look to Norway where 37% of new vehicle sales are electric because of big incentives.