I'll point out that nothing stops you, with any service at all, from encrypting yourself then backing that up. Ie., it's completely fine with Backblaze to dump

I'll point out that nothing stops you, with any service at all, from encrypting yourself then backing that up. Ie., it's completely fine with Backblaze to dump everything into an encrypted sparseimage first, and then back up that rather then your drive directly. That's not to say getting a couple of simple external USB HDDs and then rotating them into a firesafe offsite once a week isn't a good idea too, or having a NAS, or any of an endless number of other solutions. But in many cases using a 3rd party cloud service has advantages, and if you take care of encrypting contents yourself so that you just plain can ignore any security or lack thereof it'll make more options available, and possibly cheaper ones. It's all just bits and bytes.