If you claim that Apple’s cloud service, as offered to iPhone users, is risky as a backup solution, I can’t argue against that.(1) But I have a feeling you are trying to say that about any cloud service. That is a bold claim, supported with questionable arguments.
An eyebrow should be raised for many of them, but I will focus on only one. Can you provide any reputable source confirming that there was even a single case of a customer, of any larger company, losing data in a cloud backup service(2) due to the company’s infrastructure being compromised by an attacker? Just one, in the whole history of humanity and I promise to shut up in this topic.
____
(1) Not expressing support either.
(2) Not a $5 VPS instance, which are not meant to protect data.