Couple good discussions of this topic:
https://youtu.be/6dwT5uWRMXQ?si=NEEpaOKfwnWQ8ree&t=117
https://www.youtube.com/watch?v=yhn1ELAqhw4
Key point: a reviewer who wants to keep his audience has to get the sound right. If they're being paid, they lose too much of their audience for it to be worth it.
These claims about audio reviewing, not about advertorials. Those are a different animal.