Grin seemed to bring in some sort of "shuffling" method to reduce traceability by allowing accounts/addresses to move funds and make them less traceable - I don't think mimble wimble fully had a complete level of privacy before that but I could be wrong.

You seem to have resuggested public key cryptography but in a different way. Bitcoin might also transition to using mimble wimble at some point (and I'm under the impression it will, or at least become more private) but I don't think they're going to be doing that yet (it might be similar to how sharding isn't done on eth yet and is planned to be activated in 4 years or however long they expect it to take now even though it's been coded on harmony for a while).