Hmm. Interesting. If something like that could be made to work in Xenforo, I'd obviously be all for it. I see no issue with borrowing cool ideas from social media, but I think there also needs to be recognition that forums are a different sort of social media from something like Whatsapp and that there is value in some of those differences. After being on Circle, which is more social media-like, for a while, I really appreciate Xenforo.
I would never do that, though. I'm too prone to cropping and editing first. So for me it would have to be take photo, store and edit in gallery, then bam.