Salesforce is forcing to use Connect REST API instead of Custom Metadata Type for Embedding Reports.

According to Salesforce Support response on this topic:

If all the checkboxes are turned off in the External Client Apps: Settings in Setup, it means that your org has not opted in to use External Client Apps. Consequently, you are not using any External Client Apps, and there are no apps accessing consumer secrets via the ExtlClntAppGlobalOauthSettings Metadata API.

Here’s a breakdown of what this implies:

1. No External Client Apps:

   • Since the settings are disabled, your org is not utilizing any External Client Apps. These apps are designed to integrate third-party applications with Salesforce using APIs and OAuth protocols1.

2. No Access to Consumer Secrets:

   • With the settings turned off, there are no external client applications configured to access OAuth consumer secrets through the ExtlClntAppGlobalOauthSettings Metadata API1.

So this embedding method is not actually an "External App", so no need to change at the moment

This Release Update does not impact our Org!