They are not perfect, but I can't see anyone who does better overall.
>iCloud backups are turned on by default
I believe it is good default, as 90%+ of their users (would) care more about accidental data loss than privacy. When that changes, Apple will change the default.
>client-side detection system for "child pornography"
Yes, that's a very controversial move. But they made it client-side because it's more private than server-side.
I think you're right about the numbers, but I don't understand why that justifies the default. Why even have a default? Why not just ask users what they want? It's not a hard question, and it even has the benefit of helping inform users about the feature.
> Yes, that's a very controversial move. But they made it client-side because it's more private than server-side.
So? Either it respects privacy or it doesn't in this kind of discussion. Lauding them for violating your privacy but not as much as they could otherwise is like lauding a mugger for only taking half of the cash in your wallet. Yeah it could have been worse, but that doesn't change the nature of their actions.