I did, but the part you quoted had it. Anyway, there's more to it than that. WhatsApp messages may be secure, but that doesn't preclude Facebook from harvesting user data. It's reasonable to wonder, why would FB pay billions of $ for a service that they intend not to profit from, and how do they make their profits? You think I'm going to read, let alone trust, their ToS?
I personally don't care. WhatsApp is already too secure for me: The usability is hindered a lot to protect messages I really don't mind anyone seeing. If I were sending something highly sensitive, I wouldn't use it either, for the opposite reason.