Even if you think what you would say is obvious, please add. This is genuinely something I think makes sense regarding local bus routes given the longevity of light rail and how infrequently routes change, but I also suffer from confirmation bias, so I’m hoping for reasons this would be a terrible idea but obviously would prefer reasons it would be an even more amazing idea than I thought.
I say if you have infrastructure for busses/cars, build out bus routes using that infrastructure. Once you get traffic to manageable levels it’s to turn consider new infrastructure for rails. Use what you got basically, anything is better than cars