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.
CityNerd posted a really good video on this topic a few months ago. https://youtu.be/H6UD9h3hEdk
His videos are primarily US-focused, but I believe this one applies for pretty much any country.
Sorry it took me so long to watch this. He essentially feels that trams are just glorified buses and identified issues with mixed traffic routes but modern teams and light railway are capable of leaving their tracks to circumvent obstacles.