Currently, there are two ways to get a STEEM Account. The first is to sign up for Steemit with a Reddit or Facebook account, the second is to create an account using CLI_WALLET or Piston and have the account permanently linked to your own account.
This is not true. It is also possible to mine account names using proof-of-work mining in which case new accounts aren't linked to anything other than the owner key used for mining.