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.
Buses for longer journeys make sense. We have a bunch of buses in London that run from the city centre out towards the green belt. Buses for those especially long journeys makes sense.
Buses are awful for long journeys. Trams for longer journeys make sense. You need the buses to get you to the tram stop.
Why not just build a train for long journies? Cheaper over time, more capacity, and reduces road dependency.