CredentialHeaderProvider is marked as primary Bean. This bean is applicable for request scope mechanism. If any of the CSP's wish to override this bean to have their own implementation for non request scope then it would not be possible as this is marked as Primary.
We want the CredentialHeaderProvider core bean for 2 cases:
1-All CSP's except azure (property "requestScope.enabled" wont be there ,match if missing = true)
2-Azure Event grid -(property "requestScope.enabled" would be there with value = true)
For the case of Service bus we want our own Thread Scope Headers and core bean is getting ignored (property "requestScope.enabled" would be there with value = false)
If any CSP wish to override this bean, they can have the above mentioned property as false.