Your statement only makes sense in with the US antitrust laws. The proxy for consumer harm the US uses is prices which is a very narrow view. This is the reason why Amazon with 90% of the ebook market could be the victim of Antitrust vs Apple. Long term competition matters even if consumers have low prices right now. EU for example works differently. These articles will give more nuance: https://stratechery.com/2016/antitrust-and-aggregation/ https://stratechery.com/2017/manifestos-and-monopolies/