I didn't trust their rationale about PINs and remote attestation somehow meaning your data is secured by a small passphrase, just like I won't trust them to not remove a useful and existing feature I already rely on for backups.
Also not mentioned, they designed their existing backup solution to require reverse-engineered community solutions to actually access your data; I have to use a Github project to unencrypt the backup and export my chats, which is something I've never had to do with any other messenger.