How did you reach this conclusion? OP never asked for unethical ideas. I interpreted "but you'd not talk about them" as "not to attract competition", not "unethical or illegal"
BTW, writing fictional reviews for money is not only unethical, it can be illegal too
I decided to put it out there because it was exactly what the OP asked. It’s something I would rather not talk about. Whether you think it’s unethical/illegal is up to you of course.
For what it’s worth, i am no longer involved with this today.
BTW, writing fictional reviews for money is not only unethical, it can be illegal too