Those within the industry understand that one of Bitcoin's most important features and perhaps its true core innovation is its decentralized structure. Bitcoin has no central control: no central repository of information, no central management, and, crucially, no central point of failure. And yet, most of the actual services and businesses built within the Bitcoin ecosystem are centralized. They are run by specific people, in specific locations, with specific computer systems, and they are susceptible to specific legal entanglements. Other than that, bitcoin is often lauded by enthusiasts for the same reason that it’s feared by critics, that is leaderless. Nobody owns it, nobody controls it, and nobody can tell it what to do. That’s what some people keeps saying that bitcoin is decentralized.
That's true. But based on your statement, I think that the term of "distributed" suits more Bitcoin than calling it "decentralized". It's partially centralized because big miners from China have all the power over Bitcoin's mining process, while whales also control a big part of the coin's supply. But, it has some level of decentralization because no single person controls the whole network. This means that Bitcoin is in fact a "distributed" cryptocurrency rather than a "decentralized" cryptocurrency. Considering that there's nothing that it's 100% decentralized, I'd say that full decentralization is just a myth.
Like it or not, there will exist some level of centralization within any system, as a few actors would gain power by using their wealth. That's what's happening with Bitcoin, as it once started as a coin accessible to anyone around the world, but now only big miners with a lot of money can participate in the consensus process to approve or disapprove certain network upgrades. Since huge improvements can be only achieved via a hard fork, they could only become activated on the Bitcoin network with the approval of the miners. And since mining is controlled by the Chinese, they'll approve what's best for them instead of what's best for the whole community.
Therefore, Bitcoin is very distant from its original vision of One CPU, One Vote. Without this, Bitcoin will become more centralized over time, I'm afraid.