They made it work in hong kong with buses/minibuses... it can work everywhere, as long as you try it a tiny bit. But no let's send billions to private company to add more 2500+ kg of metal that displace a single 70kg meatbag, such a waste of resources and energy
Is it not simply a density problem? HK is a very different beast or any other major dense urban area. Dallas is a sprawling with an urban communities and office buildings.
So what? One day the excuse is "it's too small", the next "it's too dense", the next "it's too large", meanwhile the 200 hab village next to mine in Poland has better bus coverage than the uni I attended in Los Angeles
https://en.wikipedia.org/wiki/Public_light_bus