While you can do command line stuff with CloneZilla, I think what they’re referring to is the TEXT-based guided user interface, which doesn’t seem to differ much at all to the Rescuezilla GUI, which only looks marginally prettier. However, there’s a few other useful tools in there, and a desktop environments, so it’s still a bit nicer to use.
100% this. OP, whatever solution you come up with, strongly consider disentangling your backup ‘storage’ from the platform or software, so you’re not ‘locked in’.
IMO, you want to have something universal, that works with both local and ‘cloud’ (ideally off-site on a own/family/friend’s NAS; far less expensive in the long run). Trust me, as someone who came from CrashPlan and moved to Duplicacy 8 years ago, I no longer worry about how robust my backups are, as I can practice 3-2-1 on my own terms.