If comfortable writing a review about a product, I’m comfortable with friends knowing that I bought it. The bigger problem seems to be critical mass of friends

If comfortable writing a review about a product, I’m comfortable with friends knowing that I bought it. The bigger problem seems to be critical mass of friends reviews to make it a worthwhile endeavor. How many similar products have my friends bought? If that small group, how many have written reviews? That subset of a subset is probably too small to be meaningful.