As governments around the world pass free-speech unfriendly social media laws, the number of platforms that still allow users to speak freely is dwindling. Here is a list of some of the ones that remain.
I don't believe that Bluesky, Mastodon, or Lemmy truly promote free speech. I haven't used the other platforms mentioned here, so I can't comment on their effectiveness regarding free speech. For me, the only place where I experience complete free speech is on my own website.