1 is true: if you control the web server, you control whether the content is published as readable by anonymous visitors.

2 is true: if you disagree, provide the name of that singular corporation. To be clear, you're always relying on corporations, but there's no single gatekeeper.

3 is not the same: if I see something published on "www.water.dcceew.nsw.gov.au" I can be reasonably confident that it is published by my local Government. If I see an X account of @NSWDCCEEW_Water then I need to start looking for context clues, most of which can be faked.