You can look at this from the product vs process perspective: is "not following the standard" a product or a process problem? It is a process problem because the issue is that the process/policy/guideline was not followed.
So ensuring that the standards are "correctly implemented" and "followed" are both QA jobs.
The confusion might have arrived because in ...
Regardless of Ian Somerville's definition there's a more obvious difference, "system" and "release" refers to different things.
System refers to the content of the activity, you can test a unit and then call it unit test, modules or subsystems then call it integration tests, or a whole system and then call it system test.
Release refers to the timing of ...
System testing of software or hardware is testing conducted on a
complete, integrated system to evaluate the system's compliance with its particular needs.
System testing falls within the scope of black-box testing, and as such should require no idea of the inner design of the code or logic.
Each release undergoes a series ...