Why hasn't Web3 produced a competitive alternative to centralized social platforms yet, despite having all the necessary building blocks already available?

Consider what's already been developed:
- Identity protocols for user verification and authenticity
- Reputation systems built into the protocol layer
- Native payment mechanisms and token economics
- Decentralized data storage and user control

So what's actually holding back the creation of a functional, scalable social network? Is it a technical limitation, an adoption barrier, or simply a matter of the right product-market fit hasn't been found? The infrastructure pieces are there—the question becomes whether the integration and user experience can finally close the gap.