It's not demonstrated by engagement. The engagement exists simply because there's no alternative: FB made new attempts to enter the social media impossible. You

It's not demonstrated by engagement. The engagement exists simply because there's no alternative: FB made new attempts to enter the social media impossible. You will not get funding and you will not be able to monetize with advertising: monetization of user generated content with ads is impossible in 2018 unless you are at least the size of Reddit.