The difference between Google and Meta is that people already trust Google a lot with their data, passwords, browser history, phone operating system.

They have a lot more to lose in introducing something as ridiculous as Muse - changing the pre-established security boundaries like not decrypting your cloud-synced passwords.

Meta on the other hand has nothing to lose in the consumer privacy/trust space. They don't have enterprise users of Muse to worry about. Anybody putting their data into their apps has clearly no regard for the at data, so they're the only one who the risk/reward might be in their favour.