No system can credibly claim to sustain massive consumer scale until proven in real life.
Even if your technical architecture supports scale and federation, these are just some threats off the top of my head:
- spam, fraud and Sybil attacks, deteriorating the experience for everyone
- infighting, forking among maintainers of core libs and protocols
- maintainers get poached by mega corps
- hostile takeovers of foundations, trademarks and auxiliary institutions
- a single entity within federation gets too large and imposes their own changes that can’t be rejected without losing majority of users or forking (see infighting)
- VC/deep-pocket subsidized competition offering free service (say eg video calls) and unlimited marketing, OEM pre-installs etc, to poach critical mass of users
I love the idea of federated systems. But I think some of us nerds think too much about tech and too little about the social and economic dynamics of the real world.