shiboken6_generator requires libllvm-11.so on arm64

Using shiboken6 fails on arm64 with the error:

.../venv-6.7/lib/python3.12/site-packages/shiboken6_generator/shiboken6: error while loading shared libraries: libLLVM-11.so.1: cannot open shared object file: No such file or directory

The problem is that llvm-11 is not available anymore on Ubuntu 24.
The available oldest version is 14.

Looking at shiboken6 with ldd shows that libllvm*.so is not linked on amd64. Is there a reason for this difference?

Python version is 3.12
Installed packages according to `pip list`:
Package             Version
------------------- --------
build               1.2.1
hatchling           1.25.0
packaging           24.1
pathspec            0.12.1
pip                 24.1.1
pluggy              1.5.0
pyproject_hooks     1.1.0
PySide6             6.7.2
PySide6_Addons      6.7.2
PySide6_Essentials  6.7.2
setuptools          68.1.2
shiboken6           6.7.2
shiboken6_generator 6.7.2
trove-classifiers   2024.7.2

I get the same behavior when using 6.6.2