I had backblaze, and it’s really a bummer they don’t support linux. The closest one I’ve found is Icedrive, but it costs a bit more. I don’t mind paying a bit more though for a FOSS solution (technially not free but yeah). I probably only have 2 TB of actual important stuff but it would be nice to have more for future.
I second B2, it just works and no horrible UI like backblazes backup app. Me personally, I use Proxmox backup server. All of my VMs run on Proxmox and I have a couple PBS around.