Hello,
My answer would tend to be no. Genesys Cloud cannot serve as a formal/native 3rd party Identity Provider (IdP).
I don't know Keycloak and what it can do/support. But an auth process would likely involve more than just "Genesys authenticates the user and sends them back to Keycloak". There is usually verification of token then, involving SAML or equivalent, that Genesys Cloud does not provide (not a formal/native 3rd party IdP).
Regards,
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Jerome Saint-Marc
Senior Development Support Engineer
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