Sure. No one says they have to make their SPRMs or github repo for the spec files publicly-accessible. Where they crossed the line, though, is in contractually preventing their clients from being able to exercise their rights under the terms of the GPL. As a Red Hat customer, you can go download the SRPMs just fine, but under the terms of your contract with Red Hat, if you distribute those SRPMs to anyone else, that is grounds for termination of the support contract. This is at odds with any version of the GPL, which applies to a lot of Red Hat's packages. This is the fundamental problem and it's been going on for decades. Only recently Red Hat began to talk more tough about it, even threatening some clients with compliance audits.
All that said, I think AlmaLinux's approach is the best one for the "clones." No damage, just community value added.