I think 30% by 2030 is overly pessimistic. I'm simply guessing but since average age of the car on the road in the US is about 10 years, cars bought today will be off the roads by 2027. In ten years it's reasonable to expect that every car manufacturer will have an electric car in every category for a price comparable to regular ICE. Considering environmental and health benefits of electric cars, together with factors like prices of gas, increase in power produced by solar panels etc it does not make sense to think that most people would decide to get the worse option (ICE). I think by 2030 90% cars sold will be electric.