In fact, I'd say it's a dead giveaway for "human impersonating AI impersonating humans". Using the hyphen as an em dash screams

I like to use a lazy variant -- it's not a double dash, or a weirdly written plus, it's a an em-dash that says "I don't even have this key on my keyboard, are you actually using alt-codes or what am I missing?". Not with a shout or a whisper, but with the quiet courage of just being -- but not an incomplete representation of a whole, but rather the fullness of that very distillation of honest, simple pragmatism. Not less, just different.

The above isn't slop. It's shit though!

Actually, in an ancient and venerable markup language that's still in wide use in certain not-unimportant communities:

- = hyphen

-- = n-dash

--- = m-dash

You may notice that he didn't use the double or triple hyphen annotations either - which is usually only used in contexts such as latex, where a post-processor goes over the output for display.