If someone else is in charge of what you can publish, or what you can read, or who you can connect with, you are at the mercy of the algorithm. This means you watch what google (or Amazon, or Netflix, or Comcast, or Zaslav) wants you to watch, you read what facebook (or google, or Microsoft, or Elon Musk) wants you to read.
If someone else controls your distribution pipe, you can only publish what google, or facebook, or Elon Musk want you to publish, and it can only be seen by the people they want to see it.