So, if someone wants to make a factual claim based on anecdotal evidence, they will typically get the reaction you have seen here.
Why is it so hard to separate the concept of anecdote from fact? Anecdote can lead to fact finding, but anecdote itself without further effort isn't worth much without actual evidence.
I can get a lot of folks to tell me about how Peter Popoff's magic spring water brought them untold wealth and riches and happiness. Are those factual claims?
First of all, that is a deliberate misquote, please don't do that.
Secondly, you are conflating the term fact with a scientific fact.
The definition of a fact is merely a thing or consequence that has been proven to be true - Merriam Webster
Now the standard of proof for it to be true is
not necessarily scientific, it can be anecdotal as well.
Thus one can make a factual claim based on subjective observation and anecdotal evidence.
Whether this factual claim rises to the level of a scientifically sound one is a different question.