Are fake reviews even a problem worth bothering with? The far bigger problem is that most reviews are just devoid of useful information. "Thing arrived and box looked pretty" is what most of them boil down to. If they are fake or not doesn't make a difference. Even a review that puts effort into itself, is largely useless when the writer didn't have multiple competing products at hand to compare. And on top of that you have the issue that products will frequently change under the hood, so even if the product was good a year ago, there is no guarantee you are getting the same thing when you order it today.

The whole online shopping landscape is a complete mess and fake reviews are really just the tiny tip of the iceberg. To really improve the situation you'd need some "Consumer Reports"-type effort that objectively evaluates a products performance and compares it to the competition. Depending on random people on the Internet to do the reviewing is kind of a lost cause to begin with.