[geuszb]

That strategy is dumb because in practice people don't mind or prefer using distinct apps for each of their subnetworks; and when these networks start overlapping in the same app, they start posting less (Facebook's problem), creating multiple accounts ("finstas" on Instagram), or bifurcating their real friends to another app (Snapchat 3 years ago).

Hell the fact that Snapchat succeeded in growing a credible threat to Facebook with a fraction of the engineering and marketing resources as Google+ should tell you how wrong that strategy was...

Each of the networks grew initially by providing an insanely better experience specific to a subnetwork (FB for alumni networks, Insta for narcissistic hobby photographers with its filters, Snapchat for horny teens who want to send nude pics, or who want to be goofy with its funny face filters...)

There were a few niches where Google+ unintentionally ended up being successful, such as internal to enterprise, and for pro photographers who liked that pictures had an option to be hosted uncompressed. But the vision overall had poor market fit and would never have latched on to a dense enough subnetwork to succeed IMO.