I disagree. Value here is a matter of quality, not quantity, and impact on humanity's welfare. Most "network-effect successful" networks have a low and decreasing signal-noise ratio, they merely produce unqualified "content" for the most part.

Tech diversity in itself is a value, even if the niche players never leave the niche for the most part. Diversity allows for adaptability in a changing environment/crisis.

I believe the mass social network epoche is about to end, as the advertisement/influence ecosystem is eating up its island's last trees. The dream of the global internet failed, for reasons we can't fix. ActivityPub is much better fitting a fragmented network.