If I use the View Reports function in Content, you can see per item in Content which students can view it and this works in combination with Release Conditions.
However, for Assignments this seems not to be the case as I set up a condtion based on a Grade Item score and the View Reports showed that the Assignment (Quicklink in the View Reports screen) was available to all students. But if I tst this with a student role, this is not the case and the Release Condition work fine by shielding the item until the condition is met.
So is it a bug that for folders the View Reports screen shows the correct number of students that can view it at that time based on the Release Conditions, but that this same principle does not work for Quicklinks (Links to tools like Assignments, Discussion, Quiz, etc.)