I would suggest setting up your own hosted auth provider (via e.g. IdentityServer 4) to retain ownership of identity secrets, then use SAML, OIDC, etc. to perfo

I would suggest setting up your own hosted auth provider (via e.g. IdentityServer 4) to retain ownership of identity secrets, then use SAML, OIDC, etc. to perform federated authentication with third party authentication and identity providers (e.g. google login, apple login, etc.) This is more complicated yes, however you are less likely to end up in a situation where a core identity provider unreasonably raising their rates results in either a significantly higher cost-per-user or significant user attrition during provider account migration. Or if you’re less risk averse just pick a major identity provider such as Auth0 and use their free plan for getting started easily. Many major providers offer “easy” migration away from their competitors and provide extensive documentation for how to integrate with their platform.