Light rail is infinitely more expensive to construct and it only takes one delay/accident and all subsequent trains after cause a log jam…vs a bus which can route around it.

A better solution uses corridors dedicated to buses that are electric powered.

Something like this was done in Colombia with these routes being connected by ground hubs, similar to subway stations.

Electric busses are actually a lot more complex logistically than electric trains. With a train, you just need a bunch of big-ass transformers and overhead wires. Expensive to install, but very reliable and relatively low maintenance over many years.

Batteries on the other hand are heavy, relatively fragile, degrade quickly, and very expensive. With a 100KWh EV, about 1/3 of the total cost is the battery, so it would likewise increase the cost of a bus.

Charging is another problem, instead of the whole system using energy real-time, you now need a distribution system that can take hundreds of busses at night and charge them all back up, requiring a massive amount of power in a somewhat short time. While it’s nice that energy is generally cheaper at night, you still need the infrastructure that can take that load.

So, it’s not to say that there’s no place for them, just that our main focus needs to be on rail in most places. There are lots of low-density places with cheap power and temperate weather that absolutely need BEV busses, but a lot more with challenging weather, older grids, and medium density that are a better fit for rail.

IMO electric busses needs to have a trolley bus infrastructure on some route so the bus is recharged during the day. Won’t cover 100% of the energy needs, but will spread out the charging time.

I feel like I remember reading about tests on a roadway that could charge your car as you drive on it, like a qi charger. If that gets hammered out, dedicated bus lanes with the charging tech would limit the cost to implement to one lane while busses still have the freedom to reroute if needed.