decentralization is not the utilitarian value of Bitcoin, it's a side-effect of its utility, though. No, the utilitarian value of Bitcoin is in everyone having enough to support a market for goods and services (we'll ignore legality of any particular good or service for the moment, but that is important as well). Their value is in if there are people willing to take them for goods and services. If neither condition exists, it doesn't matter if they are decentralized or not, they completely lose their utility and hence, their value.
On the contrary, the decentralization of Bitcoin is what has allowed it to grow and flourish on its own merits (as people come and go in its development, as it's initial founder Satoshi demonstrates themself(/ves) ) and in turn encourage a market to also grow on it's own merits. Were this not the case than other fiat currencies like the USD would have sank on those same merits in the Great Depression of the 1930s (Bullion being the equivalent of Bitcoins in the days before the Internet) as opposed to being what it is today thanks to the Centralization of it by the US Reserve bank (even outright confiscating Gold to keep demand in place for said currency).
Without that value, people would not trust in Bitcoin and it would have died a premature death (or be boxed out by other interests, see the Liberty Dollar as an example of that).
TL/DR: To call the Bitcoin community a side-effect is simple ignorance.