Please branch and build scipy in epel9. If you do not wish to maintain scipy in epel9, or do not think you will be able to do this in a timely manner, the EPEL Packagers SIG would be happy to be a co-maintainer of the package; please add the epel-packagers-sig group through https://src.fedoraproject.org/rpms/scipy/addgroup and grant it commit access, or collaborator access on epel* branches. I would also be happy to be a co-maintainer (FAS: jonathanspw). I can be the primary contact for EPEL (FAS: jonathanspw).
scipy can't be packaged for EPEL 9 because it already is in RHEL/CentOS Stream 9: http://mirror.stream.centos.org/9-stream/AppStream/x86_64/os/Packages/python3-scipy-1.6.2-8.el9.x86_64.rpm