This is what was agreed to in the api review, so I'm reluctant to change that. But if we were to do so:

providerId has prior art (UserINfo, AuthProviderConfig, getProviderConfig, deleteProviderConfig, updateProviderConfig) so I'd prefer to leave that alone.

providerUid however does not. Although a bit overloaded, we could use simply uid here instead. I think it's sufficiently clear.

If we do want to change this, we should also revisit the bulk get PR which uses similar names.

wdyt?