Cloning is not backup as you usually can not rebuild a new computer from it. In most cases that means a loss of operating system, users, applications, passwords, serial numbers etc which can be weeks of work. TimeMachine will rebuild everything on whatever OS and hardware you happen to be using.
The clones made using Carbon Copy Cloner can be used to cold book your computer, (on a Mac you hold down the [Option key] to chose which drive to boot from). I test this aspect of the clone I make occasionally. It's a useful feature when upgrading operating systems because you can switch back to the previous operating system if you please, or perhaps you may have software that won't run under a new operating system (a problem that some have had with Sierra), you can re-boot and run the old version under the previous operating system on the clone. Admittedly, sometimes jumping back and forth between drives doesn't always allow you run some software which is able to restrict the operating license to one drive. But the clone does give you a source that you can copy the software back to the licensed drive, (or you can run them on the clone if you re-enter the registration key)
You can also at any time, access any or all of the data, nothing is encrypted so I am able to access the data on the clone with other computers. In fact, I think that you could even access the data on the clone from a Windows computer if your drives were formatted to FAT32.
This is seems pretty versatile to me. I don't see how this would NOT be considered a backup in every sense of the word, or how would it NOT make it easy to "rebuild a new Computer"? I'm not questioning the value of the Time Machine, I run TM myself, it allows you to access previous versions of your data, while a clone is a "snapshot in time". But the TM is not the the only answer to backing up your data. If you develop bad sectors on the drive you are running the TM on, you may lose the entire backup, while on a clone you would be limited to losing the file(s) written to those sectors. So, you make multiple clones and store them in multiple places, etc, etc.
Here is an article goes into the pros and cons of TM vs Clones: http://pondini.org/TM/Clones.html
Neither the Time Machine nor clones are the complete answer to backup security by themselves, I think it's best to do both.