My take on this is no they don’t. As long as they are truthful they only report on the quality of the product and prevent many people of spending a lot of money from losing it by buying something that doesn’t work.
If your product is shit your company does not deserve to be shielded from the backlash, this is the core of (classic) capitalism after all.
Yes, my comment assumes the reviewers are being genuine. However, in a lot of cases, those people can be weeded out and themselves fail over time because they, too, are peddling bad products (reviews).