Extremely stupid decision to rename it. Out of all their products only Oculus has overwhelmingly positive brand name, I don't know why they will want to change that. Would make more sense to build stuff around the Oculus name.
And anecdotally, IG users seem to feel very positively about it in a way that isn't true for fb or Twitter users. Most of the handwringing about IG that I've seen comes from commentators
You are right about WhatsApp though, it aslo largely has a very positive image till now