Being a system administrator isn't a scientific endeavour where the goal is to seek truth. It's a practical endeavour where the goal is to reduce risk of bad things happening. Sometimes, that means blindly following the advice of reputable people who hint at severe vulnerabilities in a piece of software, even though they can't disclose enough to prove that a vulnerability exists yet.

Keep having atop installed until you get absolute proof that it can be exploited, if that's what you want. But the organization whose systems you're administering might not like the fact that you were forewarned and didn't act.