The greatest threat to business, is business, itself — specifically a handful of companies that can control access to nearly all customers.
In most of the pre-Web days (B.W.), some companies controlled their own business and brands — certainly in the B2B space and the B2C companies which had the most valuable brands. The rest had to deal with mediated relationships to their customers. Unless a business could afford their own stores or “brand temples,” they had to play by the rules of grocery stores, department stores, and ultimately big-box stores who controlled access to their customers. These “platforms” set prices (or heavily influenced them), controlled placement (and, therefore, experience), and owned all data resulting from transactions. All companies who didn’t speak directly to their customers, through showrooms, dealerships, their own stores, or direct sales, were at the mercy of these platform owners. You know them: Sears, Macy’s, Safeway, Whole Foods, Target, Walmart, NBC, and the like. They ran valuable businesses because they owned the customer relationshipand, therefore, the best value that could be derived from those relationships.