See, the 'no evidence' is used as a rhetorical device to make something 'appear' true.
Falling back on the old 'all evidence is questionable' because our eyes can deceive, and all perception is subjective, so all of reality is in doubt, is a rabbit whole.
Sure we live in a 'numinal' world. That doesn't mean we can't use thermometers to tell the temperature, even thought temperature itself is a construct.
Of course, you can absorb information, observations, into your brain, and make judgments, like the road is wet, the light is red. It is fairly subjective, not recorded. Whether you report to the police that you swear the light was green. or Crazy uncle says aliens ate his turnips.
They are really almost about the same level of verifiability. Then it is just probabilities that make us really dismiss the alien hypothesis.
That is a lot different from forming a hypothesis, performing a controlled experience and taking measurements to prove/disprove hypothesis.
When troubleshooting, I will take in all observations, no matter how strange. But I wouldn't say they are the problem without further verification.
I think there is evidence: https://news.ycombinator.com/threads?id=ironmagma
Trolls would reasonably able to be detected by the contents of their posts/comments. Looking over the comment history, I see an absence of evidence that they are a troll and, in this case, absence of evidence is evidence of absence [because we can reasonably exhaust all of the "trials" [past comments]].
I've seen plenty of people watch the exact same debate, and each believes 100% that their side wont hands down. Of course "there is no evidence" one side won or not.
The point is that "there is no evidence" is being used to promote the opposite views.
So I can disparage ironmagma in a title of an article, and all the reader who flips through them is left with impression that "ironmagma must be a troll, lot's of good people think so, and there is no evidence he isn't".
I probably should have come up with better example. But there is "no evidence" that the outcome would be different.
That's also why we avoided eating non-poisonous tomatoes for centuries leaving food proverbably on the table. The world experienced far more rapid progression when we started demanding reproducible evidence for reproducible events.
We should have different standards of evidence for different scenarios. If Bob ate a suspicious species of carrot and ended up in the hospital, that's a reasonable indication to not eat that type of carrot, even though it's not a controlled experiment and technically anecdotal evidence. You don't need N=10 people to end up in the hospital to listen to a story.