My understanding is that if you redistribute the source they provide (whether Paywalled or free dev account) that they can and plan to 1) revoke your payed support access or 2) revoke your free dev account.
That means that people are inevitably going to share out RH source from free dev accounts right off the bat, and just cycle through new dev accounts. That’s an escalating war where they watermark/fingerprint their source so they know who’s redistributing, and any model or distro built on this won’t last or carry considerable risk. Enterprise customers are unlikely to take this risk, though. So this sets up a pretty stupid game and generally goes against the spirit of FOSS if not the letter.
I’d like to address one statement you made above: CentOS Stream is NOT RHEL source. It’s effectively the beta branch. Which means it’s not bug-for-bug which is quite frankly critical to any dev, enterprise or otherwise, and the key reason they moved it upstream of RHEL - because it screws over what they consider to be freeloaders on purpose. They may be targeting other distros, but it affects all developers who just want to test their applications. Now that dev has to explore options for a dev account, be careful not to redistribute or lose that access, etc.
Jeff does an excellent job of explaining it and whether or not RHEL contributes to the kernel or other source, stating it the way you do is akin to giving them an excuse. Oracle contributes. Users contribute (by testing, submitting bugs, providing guidance and configuration templates or advice), Countless Devs contribute. All of that should not excuse IBM Red Hat’s behavior because they want to squeeze more profit out of a model that’s not setup well. The fact that their SNAP is essentially “trust me bro” now and with this move, I’m done with anything dependent upon RH. That may not mean much in my home lab setup with maybe a dozen boxes, but at work, I am in a position to influence thousands upon thousands of instances and I’m just one person paying attention to this. RH is focusing on short term profits over long term health and without disclosing anything, I’m confident will swiftly bite them in the ass. And it will be their own doing.
Edit: I should also note that making CentOS Stream the beta sets them up for potentially new customers who do not want to be on that bleeding edge - which is a risk most established enterprise is unlikely to undertake over the more stable RHEL, which will fill their coffers for the support model.