5-9% per star
A one-star rating change moves revenue by a measurable amount
Michael Luca's Harvard Business School study of independent restaurants found a one-star increase in Yelp rating associated with a 5 to 9 percent increase in revenue. The finding is restaurant-specific, and it is the closest peer-reviewed measure of what a rating is worth to a restaurant.
Harvard Business School · Michael Luca, 2016 — Reviews, Reputation, and Revenue: The Case of Yelp.com (Working Paper 12-016)
Off topic
Complaints about things you do not control are reportable
Reviews about a third-party delivery driver, a ticketing site, the weather or another venue with a similar name are off topic under Google's published policy, and that is the ground the filing uses.
Google Maps Help — Prohibited and restricted content policy for Maps user contributions
16 CFR Part 465
Buying reviews to bury a bad one is a federal violation, not a shortcut
Since October 21, 2024 the FTC rule on consumer reviews bans fake reviews, insider reviews presented as customer reviews, and paying for positive or negative reviews, with civil penalties available per violation. For a restaurant that leaves two lawful moves: earn real reviews, and report the ones that break platform policy.
U.S. Federal Trade Commission, 2024 — Rule on the Use of Consumer Reviews and Testimonials (16 CFR Part 465)
Policy grounds only
Google removes reviews that break a policy, not reviews you dislike
Google's own help documentation says any review can be reported but only content that violates its policies is eligible for removal. That is why a case starts by matching the wording to a named policy: fake engagement, off topic, impersonation, harassment, personal information or conflict of interest.
Google Business Profile Help — Report inappropriate reviews on your Business Profile