Starting a test where posts from Threads accounts will be available on Mastodon and other services that use the ActivityPub protocol. Making Threads interoperable will give people more choice over how they interact and it will help content reach more people. I'm pretty optimistic about this.
I have my problems with Meta, but I'm hoping this will help Mastodon grow
Reading the article, they collect the data necessary to federate with an instance. If you or I were to run our own instance we would have access to the same data.
If they were to do anything with that data that they don't have permission to do, like selling it. They would be in breach of the GDPR and fined 4% of their global annual income, and as we've seen with Apple, it's not profitable to have two wildly separate versions of your product.
But again, Meta is first and foremost an advertising and data harvesting company, and many people aren’t happy at the idea of being subjected to this treatment from the vantage point of their own servers.