Pairwise Identifier is like persistent Identifier of SAML. Goal is to release same identifier for each person in various websites ( though different subject identifier for each websites ). I haven't used pairwise id for authorization but it's a good thing to test for sure.

OpenID Connect offers two types of subject identifiers: public or pairwise. With Public Subject Identifier, the sub=claim is the user ID or equivalent, e.g. sub=will. This allows the possibility of correlating user activity across multiples sites. The Pairwise Subject Identifier allows each client to get issued a non-reversible hash of the sub=claim, which prevents correlation of a specific user across multiple sites.

Thanks to answer.