Earlier quoted context omitted.
Why? What compliance reasons make Ubuntu LTS work and RHEL not work?
Stupid auditors/pentesters really. Explained a bit in another comment, but essentially we had to explain the concept of backporting cve fixes to the same 'version' of random libs to the auditors and to get certified we would have to demonstrate, with actual source, that each of ~200 or so cve's were fixed in various system parts (individually). In the end, we just went with ubuntu for those nodes, and they all passed…
The bottom line really is plenty of auditors I've seen don't know how to check for vulnerabilities other than by checking a version... That's it.. Their tools or reporting only know package must have a version greater than x.y.z.