I think this is a great take that I hadn't considered. A lot of what I used twitter for was a short blurb and link to a site with more info. So if threads can be a forum to bring people to the fuller content of Lemmy, Kbin, Pixelfed etc, it might be useful.
Even if they go full evil (and we know they will) and try to disconnect into a standalone platform the user base will still be fedi-friendly and might create a Mastadon/Kbin account to keep seeing that content.
My biggest concern is about the vibe-check though. Right now things are super supportive and friendly, Reddit-lurkers (like me) feel safer here. From what little I'm seeing on threads already (second-hand) the early adopters have some seriously problematic personalities amongst them. And I'm watching closely to see if Meta does their typical "shit floats to the top" algorithmic moderation.