@BrodieOnLinux
Although I agree that most instances need to federate, not all should.

Many smaller instances don't want to deal with a sudden influx of new users to federate with. In these cases, they may not have the funding to pay for more resources.

I've also heard of people saying they don't believe Threads is moderated enough and worried about actors. Some groups are targeted more often and a small number of malicious actors on threads could easily outnumber a smaller fully bad instance.