Everyone always says "this always failed because it didn't do X," where X is anything they like.
It's clear that it failed. It's less clear that the reason is necessarily any of the ones you gave. Every dominant social network has been a walled garden, and, contrariwise, every attempt to create a major social network based around federation and open standards has, so far, failed.
Don't get me wrong, I'd love to see one succeed, and who knows, maybe Mastodon will overtake Facebook one day, but I don't see any evidence in the Google+ shutdown that suggests that this is the case.
Mastodon and Diaspora are both horrible names for anything aspiring to be socially popular. The former conveys something lumbering, slow, and now extinct. The latter sounds like a gastrointestinal disease if you don't know what it means, and conjures up images of a group of people being expelled or fleeing if you do.
Everyone always says "this always failed because it didn't do X," where X is anything they like.
I didn't say "it failed because it didn't do X". They said "... failed to gain developer adoption ....". To that specific point, I contend there is a clear and direct causal link between the decisions they made, and that lack of adoption. Of course I can't prove that in the strictest sense, but it's not hard to see that a lot of (potential) G+ developers kept asking and asking and asking for usable APIs and never got them. Speaking only for myself, as somebody who was initially a G+ fan and might have been inclined to build things on top of G+, I never did so for exactly this reason. Yes,"n=1" and all that, but a lot of other devs were very public with their position on this as well.
Obviously their decision to close it down involved multiple factors, but the lack of developer adoption was specifically called out by Google as one of those factors.
You're missing (or ignoring) a lot of historical context in your analysis. Google spent many years trying to compete with Facebook assuming that open standards were the thing that would win. ActivityStreams and PubSubHubHub are just two examples of federated standards that they built to compete, and that failed.
Google+ came out, if you'll remember, at the time that Page became CEO again and pivoted the company's direction away from standards and more towards product. In the case of social that clearly failed. In the case of Android it did not.
Yeah, I remember that, and I didn't intend my post here to be a detailed "analysis" of the entirety of what happened with G+. I just wanted to respond to one particular point that the author of the Google post made, vis-a-vis "developer adoption".
It would be fun to spend some time doing a more detailed analysis of the whole thing, including all of that historical context, but I don't have the time right now.
Before those two, more than a decade ago, Google also had OpenSocial, with MySpace and others. It was an interesting period of time, if you were there. The project was one of the "failures" that soured Google on having open standards at all costs.
It's clear that it failed. It's less clear that the reason is necessarily any of the ones you gave. Every dominant social network has been a walled garden, and, contrariwise, every attempt to create a major social network based around federation and open standards has, so far, failed.
Don't get me wrong, I'd love to see one succeed, and who knows, maybe Mastodon will overtake Facebook one day, but I don't see any evidence in the Google+ shutdown that suggests that this is the case.