Take it with a huge grain of salt, but also note that Apple sends more personal data to themself than Google according to that article. Not in the amount of bytes, but in they amount of different data send, according to the article.
I think most people would agree that fewer personal details being shared is more important than the amount of data used to communicate. So in that regard Apple is worse.
All in all, I think this whole discussion is pointless. Both are collecting as much as they can get away with and both suck when it comes to privacy.
Of course that's at this point in time. Tomorrow Apple could turn around and be worse.