You do realize that logistically there is no way for public transport to pick you up at your front door, and at the same time pick up other people and get everyone to work in time, for example for me work is 30 miles west, for my GF work is 35 miles northeast. Logistically there would need to be different work time windows or people would have to move into regions based on where they work, neither of which will ever happen. You'll have better luck at waiting for L4 autonomous transportation on demand (Think self driving Uber).
The other issue with electric public transport is recharge times, right now EVs have the downside of charging times, you can't have a whole bus down because the battery needs to recharge. We can sit here all day long and say that supercharging can offset that but I still can't put 400 mi back into my car in 5 min. Owning an EV comes with inconveniences like that, which a tax incentive helps get people on a car they normally wouldn't think of.
I'll give you the GG tax point, however that tax is not applied to every car and it's a measly $1k which gets included into the lease/loan, which doesn't really discourage anyone from buy a GG. Secondly oil and car manufacturers would shut any higher taxes down in the blink of an eye before it even makes it off the house floor.