OpenAI is hardly a Goliath. It has no real moat, and is trying to build a business around a feature. But other businesses already have platforms with billions of users to deploy those features to.
As others have pointed out, we should see the forest from the trees. Microsoft is a huge OpenAI redistributor, also Apple. Everyone knows ”ChatGPT”. While the company size might not be monopoly, based on a larger userbase, it is.