>Modern social media leaves a very big gap - that was filled by old Facebook, or to some extent MySpace: The "people directory" where basically everybody has a page, and you can see what friends are doing, or look up acquaintances and strangers.

This was Social Networking 101 and Zuck got it right and he won big but there are so many different forms of social networking that are possible and are happening today like ephemeral content(Snapchat), short videos(TikTok) etc.

Video was and still is huge opportunity and you could see that from the astronomical rise of YouTube since 2005/2006 till today. YouTube is the second most popular search engine in the world and the second most visited website in the world.

Speaking of TikTok; the rise of TikTok was inevitable since Vine was also huge video opportunity but Twitter simple blew it away. If Vine had good leadership TikTok probably wouldn't exist or it wouldn't be as popular as it is today.

And also YouTube and TikTok are sort of hybrid social networks in a way that they are modern form of TV entertainment platforms because you can passively watch videos and get entertained nonstop without interacting with anybody. So they are not really at the same conceptual level as Facebook is.

>I think it would be hard to start something like this again, because people are afraid of data collection now in a way they weren't in 2006.

Then why the hell all wannabe successful people are on LinkedIn aka the directory of professionals. They keep signing up every single day because they want to be looked up and found by their fellow professionals and potential employers.