Generally not, and it should be 0…*, which I will fix in the Entity model. The way it should work is that most of the type, the Agent (i.e. real Person, Org etc) will have identity/ies, and occastionally a Role of the Agent (what is called ‘persona’ in the new model) will have an identity, which for that role, overrides the Agent’s ‘real’ identity. E.g. a stage name, nickname etc.
EDIT: indeed, it might be argued that there should only be 1 identity for an Agent, and maximum one per Persona, but it’s always risky to over-constrain…