Installing rail is super expensive and limits you to where the rails is and the capacity of the track. Great if you have it but installing more of it involves m

Installing rail is super expensive and limits you to where the rails is and the capacity of the track. Great if you have it but installing more of it involves many billions of dollars. I could see a use-case for e.g. Amazon using this at scale to move goods around. They currently do this at great expense by flying planes around. I wonder what the deal is with the economics. People were doing this routinely a century ago and it worked then. What's holding this back now? I've been reading about zeppelins making a comeback for decades now. And somehow it never happens.