I don't know about that. In my case I'm backing up a backup, so I have to lose both backups. B2 is just for the offsite copy of the backup. Like taking a tape home sometimes...

A backup has redundancy already - your local copy + the backup.

(edit: I’m talking about geographic redundancy. B2 does use redundancy inside the datacenter to protect from drive failure, etc)

In fairness backing up is the last place I want to hand over redundancy responsibility. Better I consider B2 as one part of the 3-2-1 backups than the be-all end-all

I guess what OP meant was that for backups durability is important and periods of downtime are not as crucial as for say catpicturegram.