You'd have to wait on it to be QA'd before it would get into Stream officially, but once it's in Stream the process of it getting into RHEL is mostly automatic. It would just be a matter of waiting, since RHEL only does releases every 6 months whereas Stream releases constantly.

With CentOS you would have the same problem, except that there's no way to make the engineering part happen any faster than Red Hat's staffing and priorities allowed.