markets are, by and large, too competitive for the "everything" app to ever exist. Air BnB works because they have figured out managing search and and a network

markets are, by and large, too competitive for the "everything" app to ever exist. Air BnB works because they have figured out managing search and and a network of "hotels". This may not translate to other services in a way that other platforms could not do better. 'Why doesn't Uber do hotels?' - type of thing.