I believe, having just CTRL-Fed through the text, as it is now, that the Fediverse would be exempt. Two caveats: 1) I may have missed something while skimming through and there are some other clauses that apply. 2) This may have a special legal meaning of which I am not aware. And, of course, this is not final.

A) IN GENERAL.—The term “covered platform” means an online platform, online video game, messaging application, or video streaming service that connects to the internet and that is used, or is reasonably likely to be used, by a minor.

(B) EXCEPTIONS.—The term “covered platform” does not include—

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(ii) an organization not organized to carry on business for its own profit or that of its members;

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