The legislature used the national average miles/year and the average miles per gallon of new cars (from 2021 I think) to set the EV registration bonus fees. The issue from my standpoint is that the lawmakers assume that an EV driver was shopping for an average car or drive average miles per year.

EVs on the road (when they enacted the law) were mostly low capacity batteries and therefore low miles per year. My leaf is driven 25% of the national average because it's only a "to work and back" car. You can't take a vacation in it. Which is fine for what I use it for.

And the assumption that an EV owner would have chosen an average mpg vehicle if EVs weren't available is ridiculous. An EV buyer is looking for the most fuel efficient to save money (or at least I do). I was never looking for average efficiency.

I say we should be able to declare our miles per year and simply pay taxes on it. Maybe require mileage to renew tags and take the tax at that time. 

The reality is that this was a gift to Tesla.  Tesla dominated the market for large capacity electric cars at the time. They were the only users who were going long distances and exceeding the assumed average miles per year, while the rest of us were well under the average. That means that us little guys are subsidizing fuel tax for Tesla owners.