Every time I see the term “SSO” I want to vomit. That does not exist any more. On my projects, there are literally dozens of systems each with their own siloed authentication systems. Just to throw out some of what I deal with: OKTA, MFA, MS 365, AWS, PIV/CACI, YubiKey, proprietary user name/passwords, IAM, OAuth, federated identity services, RSA, just off the top of my head. My single biggest fear is losing some or all of my credentials in sone catastrophe, so I keep my credentials in multiple places, including on my own phone and everyone else I know does the same thing. I have tried using password managers but one time my password database got corrupted and I lost everything, so now I just use plain text files - all of which is behind locked systems anyway (including my own phone). It’s maddening.