At which point, we'll discover that selling such indemnity guarantees as part of software is ludicrously unprofitable and unsustainable, just like the insurance

At which point, we'll discover that selling such indemnity guarantees as part of software is ludicrously unprofitable and unsustainable, just like the insurance industry has. There is not a software tool which on its own can defend against ransomware. The most robust defense requires a total system design of "Continuous Restoration", with everything backed up, with backups stored in such a way that they cannot be destroyed, with backups constantly being restored to production, and with periodic human monitoring and manual confirmation that the system is working.