RHEL 9 and its derivatives are no longer distributed with python 2. Two scripts specify python2 as their interpreter:
contrib/scripts/gerrit_checkpatch.py
lustre/scripts/zfsobj2fid
I did attempt to create the distribution with tests and i/o kit disabled, but the lustre-client-dkms RPM still required /usr/bin/python2.
I modified the interpreter to python3 for those scripts and tested. The RPM will no longer requires /usr/bin/python2 and can then be installed on rocky9.

#!/usr/bin/env python2

becomes:

#!/usr/bin/env python3

When I looked for previous issues related to this, it appeared that 'python' was changed to 'python2' for debian builds. I didn't test these scripts with python3.