Typing your username and password into a 3P website so it could crawl your contacts was horrible anti-pattern.
(I work for an auth vendor, so where I stand depends on where I sit, to some extent.)
I've seen and built apps that only needed built-in framework or language support. Or, best of all, don't use authentication at all.
I've also seen and/or built apps that needed advanced functionality to support business requirements. For example, if you want to:
* support slack-like workspace switching functionality for a single user
* but allow each organization to control the login methods they want to allow, including magic links, SAML, OIDC, LDAP, etc
* and make all APIs securely and scalably available to single page applications and mobile applications
* across hundreds of thousands or millions of users
You're going to want to use some of the more complicated standards. Basic auth ain't gonna help with that.