An example of what, the existence of other forums? Hacker News.
An example of different styles of moderation on the same platform? Reddit. Some subreddits are very loosely moderated, some are strictly moderated. See: /r/politics vs. /r/askhistorians.
An example of people moving to alternative platforms? Plenty of Youtubers are advertising their content on their own domains or services like Nebula because Youtube's own algorithms make monetization unreliable. Whang and Corridor Digital are two examples I can come up with off the top of my head.
An example of multiple points of view being expressed on large forums, despite the existence of fact checking? That should be obvious - discussion about these topics was never actually stopped or even hindered by the presence of fact checks. You can still find plenty of anti-vaxx content on every platform.
An example of different styles of moderation on the same platform? Reddit. Some subreddits are very loosely moderated, some are strictly moderated. See: /r/politics vs. /r/askhistorians.
An example of people moving to alternative platforms? Plenty of Youtubers are advertising their content on their own domains or services like Nebula because Youtube's own algorithms make monetization unreliable. Whang and Corridor Digital are two examples I can come up with off the top of my head.
An example of multiple points of view being expressed on large forums, despite the existence of fact checking? That should be obvious - discussion about these topics was never actually stopped or even hindered by the presence of fact checks. You can still find plenty of anti-vaxx content on every platform.