I don’t think Fedora users care all that much about having the latest CPython powering their systems. (And developers, venv users, are fine – they can use new and old CPythons packaged without system integration.)
But, as part of releasing Fedora, all the packages are re-built with the new CPython version. This tends to uncover lots of issues both in CPython and projects that use it. We had 500+ bug reports for 3.8 – very many were not CPython issues, but we did get good overview of how AST changes, buildsystem changes, API removals, kw-only args, vectorcall, XML ordering, etc. affect the ecosystem.
Release alignment affects when we can do this (alpha/beta/rc), and how long we have to help finding and fixing the issues.
It’s certainly possible to do the testing in other places, or by other people. I don’t want Fedora to dictate CPython’s release cycle. On the other hand, there are benefits of aligning with a project focused on integration – hopefully enough to keep this in mind as one of the factors.