Still more cost efficient to run a single bus than separate vehicles, just in maintenance alone. Also we already have buses, these single occupation EVs that still have enough space for a decent battery size don't exist.
These seems reasonable, but I don't think the math holds up. A 2016 study (http://www.columbia.edu/~ja3041/Electric%20Bus%20Analysis%20...) showed the lifetime cost (including maintenance) of a bus for its 12 year useful lifespan to be $1.4 million. Without even doing the inflation adjustment, that could buy at least 12 electric vehicles. Those 12 vehicles could be much more efficient even running on a single fixed bus route (i.e. more frequent schedule), or (more likely) operating like taxis by taking people to and from exactly where they want to go.