Vitalik Buterin argued that pluralistic identity systems are best suited to approximate the ideal N² cost curve, offering flexibility to generate multiple identities without giving users unchecked power to create mass pseudonyms.

Quotes that support claims

Pluralistic identity can be explicit (eg. social-graph-based) or implicit (multiple types of ZK-ID, no single type gets near 100% market share).

This ideal is difficult to achieve in practice, but the right kind of ‘pluralistic identity’ comes close, and is thus the best realistic solution.