Earlier quoted context omitted.
I have Photos set to download all the files locally, and those get backed up with Time Machine and Backblaze. People forget even s3 will lose files. The reliability is high sure but it’s still sub 100%
Has S3 ever lost a file yet? I know that the reliability isn't 100% as that isn't possible in the real world. But I've never heard a report of a file that was confirmed as stored being lost, and I was under the impression that this was in the category "bound to happen eventually, but hasn't happened yet".
But with cloud systems you can always lose your files when a hacker gets access to your root account and holds it hostage, or you lose the phone with the 2fa secret on, or your payment doesn't go through and you miss the reminders, or your account is wrongly closed for abuse by a malfunctioning bot.