The reason for choosing rclone was for a) performance and b) to support OneDrive. But that was about 1,5 years ago. So, when moving to full ransomware protection I’ll also test with the performance of build-in sync-to commands (at least for backblaze which is the primary destination).
a) Performance
b) To support OneDrive as a destination.
To also sync the kopia repository server that serves multiple clients to MS OneDrive (where I have 1TB storage that does not require paying extra for) which is not supported by kopia itself.