Don’t use cloud backup services to make copies of your Time Machine volumes. Here’s why
Time Machine is a simple and generally effective way to make an ongoing archive of a Mac’s files and folder structure. But it’s only a single copy of your data. The same goes for third-party apps that can clone a drive (make an exact duplicate) or make incremental archives that let you retrieve a snapshot of the current state of a volume or older versions of files that have been modified. These packages include Arq, Carbon Copy Cloner, ChronoSync, and SuperDuper!, as well as many others.
That single, on-site copy is a problem. It’s why I’ve recommended for many years that people also use a cloud-based backup service that has robust encryption. My current top pick for home use for price, performance, and encryption options is Backblaze, but Carbonite and iDrive are also contenders depending on the features you need. CrashPlan’s makers, Code42 Software, shut down its personal backup offering, but has an option for small-to-medium-sized businesses that some people transitioned to.