Federating or not federating with Threads in the context of them “slurping data” is a ridiculous discussion. They can just stand up a Lemmy instance at billjoejimbob.com and slurp it indirectly out of there.
They get very little if they’re not hosting.
Defederating means that Meta won’t be able to use everyone else for content generation.
So less people will join Threads because there’s less content if no one federates them
Threads has been live approximately three hours, now. I see at least two people who have amassed over 100K followers. Several in the 50 to 90K range and 10K+ followers for miles.
The idea that defederating them is going to deprive them of content isn’t a threat they’re likely to be concerned with.
I’d be more worried about just the general polluting of sites like Lemmy with Facebook type garbage more than anything else personally.