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.
Hong Kong is around 5x the density of Dallas.
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