I can’t point the exact signs because the message got removed, but a common sign is labeled paragraphs:

“My take: so and so.”

“The key idea: so and so.”

There are also some common sentence structures, like the format “it’s not A, it’s B”. For example, “this is not important; it is essential”.

Some words also tend to appear very frequently, like the verb pretend: “this is John no longer pretending he’s dumb”.

Any of those examples could appear in legitimate human text, but when you see many of those signs in a short text it’s very obvious.