Bootable backups have been deprecated for several years
While some developers seem surprised by a change in macOS 15.2, we've known for several years that making bootable backups would eventually become impossible. We shifted CCC's strategy away from relying on External Boot so our users wouldn't be affected by this inevitable result.
I took a few days off last week to help a family member, and returned to find the Mac community all aflutter with comments about bootable backups not working after the 15.2 update and comparisons of Apple to The Grinch. After reviewing a lot of comments on this subject, I felt it was time to weigh in. Apple is taking a lot of heat for this "bug" in 15.2, but if there is any finger-pointing here, I think it should be directed towards any developers that have misled their users into believing that ASR and "bootable backups" had any place in a backup/recovery strategy post-Big Sur.
This result does not come as a surprise
Several years ago I wrote a blog post about the macOS Big Sur changes that affected how third-party developers would be able to make copies of the System:
Beyond Bootable Backups: Adapting recovery strategies for an evolving...