Yes, the problem with Myanmar is that the most strategically valuable parts are also the farthest away. Chinese influence is strong in the border regions, but much weaker along the coast. Instead of direct control, the better approach is to leverage influence with whatever government controls the coast. Which is what they are doing right now, of course.
Myanmar is too big and too populated to be absorbed like that. It would need to be conquered, which brings us back to square one. The juice is not worth the squeeze.