The command cf enable-service-access may throw an error "Service offering 'service-name' not found".
> cf enable-service-access spring-########-services
Enabling access to all plans of service offering spring-########-services for all orgs as user...
Service offering 'spring-########-services' not found.
FAILED
➜ spring-petclinic git:(main) ✗
> cf enable-service-access spring-########
Enabling access to all plans of service offering spring-######## for all orgs as user...
Service offering 'spring-########' not found.
FAILED
➜ spring-petclinic git:(main) ✗
> cf enable-service-access spring-########-mcp
Enabling access to all plans of service offering spring-########-mcp for all orgs as user...
Service offering 'spring-########-mcp' not found.
FAILED
The error "not found" may be confusing, but it's actually indicates a permissions problem. The account executing cf enable-service-access <service-name> must have administrative permissions (i.e. admin_user instead of user) While this may seem to contradict the notion of "self-service" publishing, it makes sense for someone with marketplace admin permissions to approve publishing to orgs and spaces where you don't already have permissions.
Tanzu Service Publisher 10.3 notes are detailed; however, one's experience while using the product may differ from your expectations.