In case it's not clear what's happening here (and from the comments it doesn't seem like it is), someone (not Meta) leaked the models and had the brilliant idea of advertising the magnet link through a GitHub pull request. The part about saving bandwidth is a joke. Meta employees may have not noticed or are still figuring out how to react, so the PR is still up.
(Disclaimer: I work at Meta, but have no relationship with the team that owns the models and have no internal information on this)