That is an orthogonal solution to SSO. I have many apps in my home lab. It doesn't make sense to have individual credentials for everything, even if it is effectively free to keep track of them. Rotating dozens of passwords (even spread out over time) is not my idea of a fun day, nor is supporting individual logins for friends/family who use the apps in my network.

SSO is the quick and easy way, especially when other people are involved.