You don't see competition driving down the prices on major brand phones, GPUs, telecom services, most online services, etc. despite "heaps of competition" because they are each creating their own walled garden flavor to create captive audiences to jack up prices on. You don't see banks competing against each other either, you get more or less the same fee structures no matter where you go. You have the oligopoly of normalized prices where the major players have captured the market and captured the market's regulators, keeping any meaningful new competition out of the market and not having any desire to trigger a price war by rocking the boat.
In the tech sector, much of that is achieved by patenting the heck out of often trivial aspects of devices and services (ex.: end-of-list bounce animation, rounded corners, whatever-you-used-to-do-over-phone-but-over-IP, whatever-you-used-to-do-IRL-but-in-an-app, etc.) so nobody else who doesn't already own a boatload of similar patents they could contest yours with can do anything similar.