That phrase is usually referring to some sort of judgement or characterization, not a particular action. If a teacher makes the whole class stay late because a few were acting up, that's not painting with the same brush. If you think that all children are disruptive because a few acted up, that is.
Ok but in both the case of HN and TOR, you're making a judgement about the kind of people on there. There's nothing inherently wrong with traffic from a TOR router, it's the users on there. HN referrals are similarly not a problem per se.
Hm, I suppose that's a distinction that can be made. OTOH, I think someone posting
> In addition, we find that only a tiny fraction of HN comments (often less than 1%) actually engage with the substance of our articles, with the majority being off-topic, misinformative, repetitive, or otherwise of low quality, making the overall value of HN exposure overwhelmingly negative for our project.