Can Luoyang be directly under the central government?

Don't think about it. It's basically impossible to be directly under the central government. Just look at the development of Chongqing (which is equivalent to the area and population of a province). With so many policies, it has only developed like this in recent years, and it may not be good to be directly under the central government. Luoyang might as well be a third-tier city honestly, develop steadily, and maybe even be able to rush to the second tier. The people have a good life and are more affordable than anything else!