You misconstrue the nature of the decentralization promised.
First, the blockchain is decentralized. Destroying it is almost literally impossible. This means your currency will live on until a predictable death, dictated by price.
Secondly, access to the network is merely technical in nature. Unlike in legacy banking, where your money is continually subject to post hoc legislature and surveillance, your access is determined by possession of private keys. Thus, control of currency is organic in nature.
Thirdly, anybody can mine. You might not make money at it, but you can at least run a full node that secures the blockchain. This keeps the network honest, because anybody can verify for themselves whether a transaction is legit.
These are the decentralizations promised. Anybody who read the white paper and had a clue about the physical requirements to mine at scale knew that professionals would take advantage of cheap electricity and economies of scale.
None of that is to say that your Cicada is a terrible idea and should be squashed. Publish it and see if you can generate a network effect.