in practice, yeah they can be only one product. ' Due to the SV playbook of using 0$ pricing to corner the market. some markets are inherently monopolistic. so yeah either favor the incumbent or favor the person, with the largest share due to network effects. network effects aren't priced effectively in the market. or neither accounted for in monopoly law. for examples look at the fight between uber / lyft / chinese ride hailing companies etc. Hence we need standardized data transfer policies or protocols.