1) What in your opinion were the main use cases for CentOS before this change announcement?
2) How do you think CentOS Stream is still viable for those use cases?
1) I obviously can't speak for anyone but myself here, but in my use case, which I think is pretty common, is to use CentOS for production deployments of various web apps and services where a person prefers the rock solid stability of RHEL without incurring the cost, and does not need support to go along with it.
2) I explain this in depth in this blog post which is up now ( https://freedomben.medium.com/centos-is-not-dead-please-stop... ), but the short version is that CentOS Stream is basically going where RHEL used to be. If RHEL was too bleeding edge for you, then CentOS Stream will be too, but otherwise it will be approximately the same as RHEL used to be. I consider RHEL and CentOS to be pretty equal, with CentOS lagging a bit behind. Now they will be pretty equal, with RHEL lagging a bit behind. Packages going to CentOS are packages that would have gone directly to RHEL previously.
There will be another small difference: the number of updates. Just for fun, I started a centos:8 image in podman, installed the package which switches it to centos streams, and ran an update (which by the way partially failed with an error message, IIRC it tried to change /proc in a way podman doesn't like). Then I looked at the version of one of the updated packages before and after the update (IIRC it was bash), and looked at its changelog. There were several releases between these two versions, and I would expect each one of them to appear separately as an update within CentOS Stream.
That is, packages that would have gone directly to RHEL previously will be going to CentOS, but not all packages going to CentOS will be going to RHEL; we will also be getting all the intermediate steps.
Do we have an official word on that? Because it feels like QA could just as easily be priority tasked on the next point release RHEL and starve stream of QA while it carries on ahead. I guess this boils down to the workflow which there doesnt seem to be a simple guide of with this news.
And no, I wouldn't agree that they just swapped places. CentOS stream is a rolling release. Unless I am mistaken that's not how RHEL is built right now.
I can see a reason for swapping them in that adding RHEL goodies/licencing into the free version is easier than removing, but the release cycle change, dropping CentOS 8 and as you admit, absolutely shambolic official press release, with lines that reek of a salesperson trying to squeeze out a bonus, do not inspire faith.