Fedora is very accessible to a new linux user. He can then switch to centos for his server needs and make his tests, to host the server of his guild for example. And then move to rhel for his job. And he will stick to Fedora for his home usage. That's a solid population to ask support questions to.
With the end of centos/clones, it means there is no testbench for servers anymore for the fedora crowd. They now have to jump to the paid rhel version or not do it at all. Centos stream is not something that you want to run services on. That's not the real deal like centos/clones was.
The hobbyists who ran centos/clones and who never jumped to rhel will also be confronted to the choice of running fedora and another complete different system like debian server. In this situation they will probably change their server distro as well and adopt the light version of it for their home usage. To emerge themselves into the new ecosystem. Why would you split your habits on 2 different type of distro?
And finally there is the trust part. If IBM can shut down centos/clones in one day without flinching, what could possibly happen to Fedora? I had my doubt during the acquisition, I don't have doubt anymore.
There is a lot of reasons why debian or ubuntu or suse will see fedora refugees coming to their shore.