to discredit a Target by questioning things they say or do (or write)
in a critical way is a common Control -domination-bully behavior. A
person needs to believe first that they are innately superior to the
person they're targeting, and must also believe that they are more
knowledgeable, experienced, smarter or wiser than the other person. "Where did you hear that?!" "I don't think that's true." "Where are you getting your information from?!" "What did you just make that up?" "Who are you supposed to be, an expert?" "What makes you think you know what you're talking about? You don't even have a degree!"
Because controllers and people with narcissism are often fixated on
finding ways to "prove" that they're superior and that others are
inferior, wrong, and don't know what they're talking about, they tend to
"interrogate" other people about pretty much any subject, and imply or
accuse them directly of "Not knowing what they're talking about" or "Not
knowing what they're doing". They won't have a discussion or ask
questions, they'll just do THAT.
It's like how some humans
will just lumber in and attack a random animal with a stick without
knowing anything about the animal, and without making contact with it
first, just because it's "there".
There's no "reason" for this behavior except for the person's own behavioral and emotional issues.