How can anyone say he “missed mobile” when he led the biggest mobile play of any software company in the world, leading to a dominant position today? Top analysts like Ben Thomson widely give him credit for it.
If he says he “missed mobile” it’s possibly false humility and actual hubris, or he means something completely different.
Facebook was still in its infancy as an internet company back then and I doubt they would’ve been able to carry out a hardware or OS play without extremely diluting its focus. But sure, if they had done so and succeeded despite the minimal odds they would be in a totally dominant position right now.
They were indeed really slow to recognise mobile as a worthwhile platform. So long that it would have jeopardised their position if it hadn't already been pretty much invincible.
Messenger as a standalone app was released in 2011. They bought Instagram pretty much within two years of birth.
The UX of a lot of the mobile products might not have been good - I don’t remember - but all things considered I would say they moved fast on mobile, at both the engineering and strategic levels, and it paid dividends.