Making their APIs easy to use like they used to be 10 years ago will be equivalent to releasing their core assets. In the past you could do almost anything from the Facebook API that you could do with their web or mobile app.
They release a lot of open source stuff as other commenters have mentioned but you can't build a Facebook or Instagram competitor just by integrating those components.
They release a lot of open source stuff as other commenters have mentioned but you can't build a Facebook or Instagram competitor just by integrating those components.