This is a fight between IBM and Oracle. There's been a lot of bad blood between them since Oracle did a s/Red Hat/Oracle/r for their own branded distribution.
IMO that's the main driver behind this change: don't feed your largest competitor free stuff and not something specific against Rocky/Alma/whoever else is using the code.
This was my initial thought as well, but I imagine that would violate the terms of their subscription and Red Hat could just revoke their access going forward.
True, but what's stopping someone from uploading it anonymously? They have to share the code with customers, but that doesn't mean GPL doesn't apply to non-customers. Anyone working at these companies can download the source code and upload it online.
Wait wait, Oracle took someone's stuff and did a lazy half-assed job of slapping Larry's name on it and then shipped it as a product they then sell seven-figure support contracts on?