First, hi, Derek! I'm so glad to be following you here.
I think one thing that federation can do *better* is tailor moderation to local cultural norms and do it more quickly.
Decisions made at Twitter headquarters or Facebook headquarters have to balance the competing needs and wants of hundreds of millions of people.
A mod for a 1k-10k instance can focus on local needs instead. They don't have to solve everything everywhere all at once.