1. it consumes too much systems resources. So its net-negative impact on the system under observation
2. it's misleading and leads to false diagnoses of situations under review
3. she's under an NDA of some kind related to a CVE or some other high class risk which will come out in due course but she felt a burden to stop people being exposed to risk.
4. I can't count and there are 4, 5, 6 other reasons but these 3 are mine.
I'll go with number 3. She didn't just say "don't run", she said "uninstall". That doesn't sound like "misleading" or "uses too much resources". It sounds very CVE-ish.
That's what it smells like but this is still a weird way to disclose something like that. I imagine some people with free afternoons are taking a stab at auditing atop's PR history right now. I'm not personally up to the task, but the fact that the top 3 contributors other than the original author are ByteDance employees might cause some to jump to conclusions.
Does atop have any legitimate need to connect to the network? I can’t think of any legitimate accidental security holes that might show up in something like atop, but then, these utilities often have funky features I don’t know about!
1) is possible because it uses some interesting options like nice/mlockall/changing its oom score so if the atop process went out of control your box would probably be fucked.