It doesn't have to be 100% decentralized to be useful though. A central server could be in charge of linking the hash to the latest ipfs directory of files. (Or

It doesn't have to be 100% decentralized to be useful though. A central server could be in charge of linking the hash to the latest ipfs directory of files. (Or they could use ipns, but let's ignore it for a moment.) But then all of the files are available from a decentralized cloud of users, from everyone running ipfs and hosting the content. And if the central server giving the latest hash ever goes down, people will still be hosting the files and people can find the latest directory hash elsewhere.