I'm not convinced that this even violates the spirit of the GPL.
Let's be honest here: Red Hat is still distributing the software widely, but it's making it hard to make exact Xeroxes of RHEL. That's a business problem, not a software freedom problem. CentOS Stream is, at least in my opinion, from a software freedom perspective just as good as RHEL.
You can use it, study it, change it, and redistribute it. AFAIK everything in RHEL makes it into Stream, albeit out of order and hard to re-assemble as an exact copy. But it's not like Red Hat is adding great features to RHEL that it denies to users of Stream.
Compare that to the Open Core folks who are trying to gang up on Red Hat now. There's the core version that has most of the functionality, and then the enterprise features are held back under non-free conditions. You have no recourse if you're using an open core product and they get bought up and the software is discontinued. You can't exercise the four freedoms to hire someone to maintain it for you or DIY it if you don't have the code.
But someday when Red Hat stops making RHEL you can still exercise the four freedoms and ask somebody else to do it for you or DIY it. To me, that's the spirit of the GPL - not that I'm entitled to undermine somebody's business by making exact Xerox copies of their software indefinitely.