China is actually working on all three at once: wearable, under the skull but not in the brain (think closer electrode, without skull, skin and hair in the way), and in the brain, each of the three has pros and cons, so it makes sense to work on all as that way you can take only the amount of risk as the need for the device justifies.

There is that and then there is the fact that the US and co almost certainly wants a literal Mind-Control device no matter what they claim, but China actually wants the Mind to remain in Control rather than Controlled, and the focus is on medical advancements for human benefit. The US will charge an arm and a leg for such, but medical purposes (or rather Medical Expenses) is secondary to how the Capitalists use anything and everything to maintain control over humanity and remove threats to their hegemonic control of the world.

An example of the US use case is in how they took “Alligator Alcatraz” Concentration Camp victims and used them for Neuralink experimentation.