To call it "completely different" is false. They are built differently, but the end result is still 90-95% the same software versions (because it has to be as the major version of RHEL). In fact, the way it is built differently is a massive improvement over the old process. The old CentOS was put together by 2-4 people at a time, with long delays after the corresponding RHEL releases, with no ability to actually fix bugs or accept contributions. The new CentOS (CentOS Stream) is built by thousands of engineers, literal subject matter experts who can actually fix bugs you report to them, or even better merge a contribution you submit. Also, the branding wasn't reused, the branding is for the whole CentOS Project, which still exists and is more active than ever. Also, you can still use CentOS in your dev environments, and it works great for that because you can prepare your production workload for upcoming changes in the next RHEL minor version ahead of time. You can also get free RHEL for dev environments, for the things you need to validate with the same minor version as your production RHEL environments.