Now Debian has a release with a useful package missing. What ever happened to orphaning a package if you didn't want to maintain it anymore? I certainly see nothing that make the claim that it isn't suitable for release justified. It is working very well and does not appear to have any serious bugs. Good thing you didn't remove it from sid. The removal from bullseye was clearly wrong and unjustified. Not the correct way to handle a package (I am surprised it got removed in fact).
As for the idea restic is a useful replacement, not a chance. That design is way too complicated and they are not even at a release where they declare the api or repo format stable. rsnapshot nicely provides a backup that you can look at with standard tools and recover things however is most convinient. And someone did just do some updates upstream and make a 1.4.4 release a few days ago. -- Len Sorensen