The growth of our app had been stagnant for a quite some time, despite being featured on ProductHunt and BetaList. We looked into search keywords, customer feedback, and analytic data in details: there are at least 5 times more clicks from review-related keywords, compared to social proof related keywords (e.g. pop up, social proof, etc.). At this point it becomes obvious to us that the social proof market is more or less saturated until we have 10x features, but the review market is not.
This is further evidenced by customer feedback we got from https://itsmybag.store/ . The customer had been looking for a widget like ours to collect and present reviews for months (along with a series of other features in the backend). We had long conversations with customers like them, and reiterated our product using their feedback. The result: happy customers, and much lower cost per lead and cost per impression.