I generally agree with your gist; however, I would point out that there are niche review sites run by enthusiasts (whether computer parts, cameras, tools, gadgets, clothing, and so on.) and there are the SEO types that are near-worthless. Enthusiast sites have a range of community-only and not ads, some have affiliate links and some have paid reviews and so on. So you have to know how the site operates and take that into account.
The niche ones have mods which allow genuine dissent as well as other recommendations from competing solutions.
I am thinking about the car enthusiast sites/forums (where you can search for information how to fix minor issues), also places like cpubenchmark, tomshardware, anadtech, dpreview, shoptoolreview and so on. You have to get to know the forum and how they make money, whether it's a labor of love or main source of income, how transparent they are about sponsorship, etc.
The niche ones have mods which allow genuine dissent as well as other recommendations from competing solutions.