Why SAML is not preferred way for SPA (Angular + WebAPi2.0) application in Okta

Why SAML is not a preferred way for Okta integration of a Single Page application built using Angular 6 and Asp.net WebAPI 2.0.
I looked for the answers online and always found that use OpenID for Single page application.

Can anyone help me with the reasons to justify?

Thanks in advance!

SAML requires an out of band metadata exchange between the IdP (Okta) and the Service Provider (your app), this is not possible if you don’t have a server side component