I have consistent behavior on Fedora 32 in mock [0] and podman [1]. Wanted to test docker as well, but my docker setup is currently broken.
# python3.9
Python 3.9.0a1 (default, Nov 20 2019, 00:00:00)
[GCC 9.2.1 20190827 (Red Hat 9.2.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.pidfd_open(-1)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
PermissionError: [Errno 1] Operation not permitted
=> the test fails.
[0] https://github.com/rpm-software-management/rpm
[1] https://podman.io/