IME the checklists and guides can be a useful resource but are mostly “cover your a$$” documentation, often time falling into cargo cult suggestions just to add more check-boxes.
Some of the line items can be a bit arcane or not as relevant in cloud environments, etc... but that's a far cry from calling them CYA.
Nothing cargo cult about enabling SE Linux, restricting access with IP tables, configuring AuditD and AIDE.
These are great ways to massively overcomplicate your system. Generally speaking, having encountered these tools, do not use them unless you're willing to dedicate about 2x the time you would otherwise spend administering the system.
Frankly you sound like the tired BOFH trope, if you don't see the benefits of security hardening I hope you are never responsible for anything important infrastructure wise in your organization.