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  1. Yes, steem blockchain is decentralized, but since everybody uses steemit.com to access it, it is unclear how "decentralized" the whole thing is. Bunch of people can dictate rules.
  2. That only results in tons of garbage content, I suspect.
  1. Steemit.com is only a UI into the underlying Steem blockchain. So it is actually decentralized...in essence you could run SteemZ.com and improve/change the UI however you choose.
  2. It may result in garbage content, but if this content is not profitable it will not continue...