@Nadru they can in principle do that with any publicly available data, and certainly with federated data too, yes. Wether they do this or not is anyone's guess.
@necrophcodr I remember that this issue came up when Threads wanted to federate but I thought Mastodon added ways to protect its users (apart from blocking them completely). Maybe not yet :(
@Nadru there's no real way to protect against it if the data is available, afaik.
@Nadru anyone can do that, even users on the Fediverse...you'll never know who has access to your posts unless you lock your account and post things privately.
@BeAware True, there is no true protection