Based on data from https://fedipact.veganism.social/ it seems that the majority of instances blocks threads.net. I'm sure there's Lemmy instances with either approach that have slipped through the cracks as the list is a work in progress.
The percentage of users doesn't correlate to instances as the biggest instance on the Lemmyverse has roughly 3x the users of the second largest, a NSFW instance, 4x the users of the biggest "niché" instance and 5x the users of what I see as the second largest general purpose instance.
It's interesting that Mastodon instances are trending in the opposite direction of Lemmy instances. Most are staying federated with Threads. I wonder if that's simply indicative of the strong anti-corporate culture on Lemmy, or if there's more to it.
Maybe that and the creator of Mastodon actively rolling out the red carpet for Zuck
Yep. Meta's convinced him that this is a huge victory for Mastodon -- and a good way for him to achieve his goal of getting Mastodon to 100,000,000 users.