This is correct, centralisation comes in power of decision making. It is why Monarchy is centralised as King/Queen can make decisions any way they like, it is why Capitalist business is centralised as the owner can make decisions any way he likes, it is why Slavery or Feudalism or State Capitalism is centralised, as each one of these has some entity that has the power of making decisions. It is the removal of this decision making from the system that finally creates decentralisation. One common set of rules which apply to everyone equally, and no one having ability/power to change them.