Not how it works. Also your use of "becomes a publisher" suggests to me that you are misinformed - as so many people are - that there is some sort of a publisher vs platform distinction in Section 230. There is not.
Repealing Section 230 would actually have the opposite effect, and lead to less moderation as it would incentivize not knowing about the content in the first place.
Back in 2001 the recruiter at my high school very nearly convinced my girlfriend at the time to join up. She was not cut out for that life, and did eventually back out.
Seems like there is a lot of people in this thread that are confused about BlueSky federating even means. BlueSky's plans for federation have nothing to do with the fediverse. It's about enabling federation with other AT protocol services, including self-hosting a personal data server.
The path forward I think would be some sort of a bridge service. Think of it as a translation layer that could take in updates from both ActivityPub and AT, and present to the opposing side like it were native. Something similar was developed for nostr to communicate with the fediverse, and it seems at least feasible in this case as well.
Unfortunately it seems like development on Tumblr has been reduced to a skeleton crew. I wouldn't hold my breath for ActivityPub integration on that front now.
New rumor? You mean rumors as soon as it was unlaunched. Nothing new about this.