Will Meta scrape and crawl through all our data now?

So from my understanding, I can block an instance which prevents it from showing in my feed.

However, if the instance I post to (.world) is not blocked on the receiving instance's end (Meta), they will still get my post (unless defederated)?

If so, doesn't that open up the idea that Meta will be able to scrape and take ALL the data from ALL the (still federated) instances' posts that are not blocked by the Meta instance(s)? How can I protect my information from Meta while still being federated, or is that not possible?