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.
A plurality of negative reviews kill those companies that make bad products. And that’s a good thing. Wheat from the proverbial chaff as it were.
Comcast is a great example.