Earlier quoted context omitted.
That's Apple's closed garden, even when they allow you to sideload application, they still have the ultimate decision. Of course it's not malware, but probably enough users have vulnerable software which could be remotely exploited, that they decided to blacklist it.
A program that surreptitiously reinstalls software when you uninstall it is by definition malware. A piece of software that lets any website activate your camera without your permission is a security vulnerability.
Malware is a software written to harm user. Their purpose was not to harm user, they wanted to make their service more convenient for users. Bugs are bugs, every product have bugs and many products have security bugs. That does not make them malware.