Packages in RHEL 8 should not use, Require or BuildRequire `/usr/bin/python3` because that file is provided by all the Python stacks - 3.6 (the main one), 3.8, 3.9, and 3.11. The particular version `/usr/bin/python3` points to depends on the system of alternatives and is determined either by the priority of the individual options or by manual setting by the system administrator. Python 3.6 has the highest priority, so if it is installed, `/usr/bin/python3` means Python 3.6 by default. However, when Python 3.6 is not installed, `/usr/bin/python3` can mean almost anything.
Python 3.6 is the only Python in RHEL 8 with a full 10+ years of support and all system packages should depend on it. All other Python stacks have a shorter support period.

We are opening this issue for all affected packages but I'm not sure whether there is anything to fix in this particular case. Until RHEL 8.7, `dnf install /usr/bin/python3` always installed Python 3.6 but now it installs 3.11. Is that a problem from your point of view? In my opinion, I'd expect Python 3.6 to be installed.