"Decentralized" means little without more context. The issuance of bitcoins isn't a legal monopoly. In this sense Bitcoin is "decentralized". On the other hand the Bitcoin blockchain is a centralized ledger, which is distributed, but nonetheless centralized. So which one is it? Centralized or decentralized? It doesn't matter because at this stage "decentralized" is being used as a mere buzzword rather than to convey a precise meaning.