But... this simply isn't true. Group transportation is the only viable way across the least dense places on earth: oceans. You almost always take a plane with hundreds of other people on it. Not to mention the fact that high speed rail is vastly superior way to get across a country than a car. Taiwan has several massive freeways running the length of the west side of the nation. The drive time north to south is between 6-10 hours depending on traffic. In the high speed rail, it is 2 hours, every time, to the minute. It moves 130,000 people per day, far, far more than the capacity of the freeways.

Exactly, retrofitting cars is not economical. Right now everyone drives combustion vehicles, those will all essentially need to be thrown away or recycled as we switch to electric. Think of all that waste. Meanwhile a diesel train needs the engine, or whole engine car at worst, swapped, and a third rail installed or overhead power installed. Every other aspect of the thing can remain the same: the cars, the tracks, the stations, everything. For a retrofit of an entire city's train transit system, you have maybe 20 or 30 train engine cars in the garbage or to be recycled, maybe some supporting diesel fuel infrastructure (the piping for which can be re-used for power transmission if necessary), that's it. Meanwhile millions of cars are about to be trashed or need to be recycled. You can't even reuse their tires.

I don't like cars, you're right, mostly because they keep killing people, but I'm really not trying to be annoying here, I literally see no advantage. Even in the USA, one of the more rural-focused countries on earth, you have a deep history of using public transit to access the remote regions of the country, that you simply stopped using over the last hundred years. I have had the delight of visiting some of these old train lines and encountered stations sprinkled all throughout places that are now accessible only by car - and some of these small towns even had street or cable cars for local transportation connections! You had it, you just got rid of it. And nowadays you can have even better - combine trains and streetcars with public electric bicycle infrastructure (take your pick of tens if not hundreds of cities with functioning examples) and you have a wonderful modern transportation system that serves the needs of people rural or otherwise, without poisoning the environment and without getting people killed every day.