On the Ice Cream analogy, if there weren't reviews of it you might not even know that pistachio-strawberry even exists.
Forum reviews are reviews too. Generally they are shorter and the authors don't write many reviews. Unless you know the person and their gear experience and thoughts, it's hard to connect the dots.
One of the benefits of formal reviews to me comes from following a particular writer. If my observations of a piece line up with theirs, +1 for that guy. If it sounds much different to me I might assign less weight to their words in the future.
These days it's hard to hear many of the options out there unless one lives in a big city. What are the choices then? One could buy only gear available for demo in their town. Used gear could inform most/all of the user's dietary habits. That's no panacea and how do we get information on used gear?
It doesn't make a lot of sense to me to seek out a particular form of entertainment, say the movies, then complain about the entire experience. You pay to get in, go through the ritual, get home, and say "I can't stand going to the movies." The easy response is "don't go to the movies".
If you don't like formal reviews, don't read them. Suspicious motives, backdoor deals, outright grift. Do these things happen? Maybe. Outside the reviewer and their immediate contacts with the company under review nobody really knows exactly what arrangements were made. "OOOOhhh, what if he got a discount on this thing he's reviewing?!?!"
Guess what? Odds are whatever discount he's getting would be gotten on whatever other piece he chooses to buy. So from his standpoint he chooses what he likes best, just like you. And, within the realm of all the things he could buy he's making his decision on what he likes and keeps just like you. With whatever discount the stuff still isn't cheap.
Each reader can decide how much credence to assign any review. The answer could be "none, I just read for pleasure" to "I buy everything that gets a good review". Of course the latter is plain silly but each of us falls somewhere along the continuum. I say read as much as you can on the forums and in formal reviews. Get some ideas, if you're interested in something, don't be afraid to contact anyone on the forums or at a publication to ask specific questions about how their experience could dovetail with your situation. Be proactive.
Or, you can sit on the sidelines and whine about how you hate going to the movies over and over and over.
p.s. Writing reviews is a lot of freakin' work. So if the writers get a little testy when folks crap on 'em that's why.