- This give Apple access to data right now. If they turn evil in the future, they have access to data from the past, which gives them more leverage.

- The security industry (overall) pays attention to Apple updates. If Apple turned evil in the future by issuing an OS update, someone might notice it happening. But if they start organizing this data and handing it off to the government, they don't need to change anything public or issue an update. They can do it all serverside without anybody noticing.

- One of the ways we tell whether a company is trending evil is that we pay attention to how its willingness to invade people's privacy evolves over time. This is a more subtle point.

Imagine that I was administering your phone. There's trust involved in that kind of relationship; if I turned evil, I could install some tracking software or viruses and violate your privacy. So imagine that one day you find out I have installed tracking software on your phone, but when you ask me about it, I say, "it doesn't matter whether or not the tracking software is installed on the phone. If you trust me not to invade your privacy, then you might as well trust me not to look at the data the software is collecting. As long as you trust me, it makes no difference what I install on your phone, since you can trust me not to use that software to violate your privacy."

You probably wouldn't be satisfied by that excuse. In reality, seeing that I am now the type of person who is willing to install tracking software on your phone should give a suspicion that I have either already turned evil or that I am on my way to turning evil.

So similarly with Apple, it's true that trusting Apple means putting them in a position where they could start collecting people's private data. The fact that we have now seen them start collecting private data means that we should be more suspicious that Apple either is already evil, or at least that it is more willing now to play with evil ideas than it used to be.