I think you're right that there's more of a critical mass requirement than real network effects. However, I think uber pool/lyft line require a much higher cri

I think you're right that there's more of a critical mass requirement than real network effects. However, I think uber pool/lyft line require a much higher critical mass of users to be effective than the basic lyft/uber services and there may not be enough users to fund more than one of those in some (many?) metro areas.