A person’s writing style is as unique and identifiable as their fingerprints. As an example, you began your comment with “Hello” rather than “Hi” or simply nothing, and also used a comma.
You then made a common grammatical error by using “This” as the subject of a sentence, without specifying — “This [what?] is standard syntax . . .”
Combine all of those tics and tendencies, and you can identify with reasonable certainty whether a person authored any writing longer than a paragraph.
In alternate, can be using word version of voice modulator from screaming movies.