With a user base of 500k if every GOS user left a review that'd make a dent.
True. But when the Volkswagen block was publicized a lot, last time I checked the number of stars didn't even decrease by 0.1 (even though there were a bunch of negative reviews). Admittedly, PayPal probably has more GrapheneOS users than VW, but with VW negative reviews could have made a serious dent.