#Signal announced cloud-based backups a month ago, so I am late to the party. Still, I wanted to write down some notes on why 4 digit PINs aren't going to provide real security, no matter how hard one tries.
Thanks to @leip4Ier for bringing this topic to my attention.
https://palant.info/2020/06/16/does-signals-secure-value-recovery-really-work/