Monopoly is when they use that market share to compete in _an entire different market_ without actually earning the "best" spot. Or using their dominance to prevent competition entirely from succeeding. For example: Blocking all ad-tracking on its own browser, except ads purchased through its own ad network. Remember, _you_ are not the customer of Google. You are the product. The ad companies are the customer. The market is not search: the market is ad sales.