Mostly you are right, but not entirely. Many of your concerns about electric cars are growing pains which means they need to be separated.
Cold weather reliability for electric cars will get better.
Battery wear out will be a problem we learn to solve - replacement batteries already exist, they just need to be factored into the cost of the car.
Most of the things you need to work on for electric cars are exactly the same as gas. You still have brakes, tires, a suspension system. The rest are things that those mechanics will learn, just as their learned to work on gas engines.
When there are enough electric cars on the road the network will follow.
You are correct that in 8 years the gas/diesel car will still dominate. It isn't clear if buyers will switch to electric cars by enough that all new cars are electric in 8 years (if the buyers don't switch the politicians will blink and repeal the 8 year law). However as buyers switch to electric cars the infrastructure will follow.
The real question is will non-cars switch to electric. The fuel density difference is just a minor annoyance for cars. For truck, trains, tractors, and other heavy duty operations the energy density is much more important.