Comment by ucaetano

> After all, consumers benefitted enormously from the phone system coming into existence.

You're mixing two distinct periods of time. When there was the expansion of telephone systems, there was no consumer harm, but when AT&T stopped others from entering the market by using its monopolistic power to prevent competition, there was harm to consumers.

Those two periods are over half a century apart.

Similarly, when SO invested in horizontal integration, it was great for consumers: the reduction in cost and standardization of plants and materials (oil, metals, etc.) created a boom.

But when it used its monopoly to prevent competition and extract rents, there was consumer harm.