It's one of the reasons that blanket policies requiring the use of a specific thing are generally bad. Often times, it's better to just have seperate systems to fill individual niches than it is to try to stretch one system to do 20 things.

MetroRail is a prime example of that. It's a system that is trying to be 3 things at once and doesn't do a stellar job at doing any of them individually. It wants to be suburban commuter rail shuttling workers in and out of the city with a focus on peak rush hour service. It wants to be a rapid transit system for the urban core. And it wants to be regional rail servings things that are really too far for subway style cars and seating like Dulles airport. It accomplishes all three but to a mediocre level.

Battery EV busses, and vehicles in general, are the same thing. They serve a niche and have their place where they win, but there are roles where Diesel or Trolley busses may be a better solution.