They had no problem deregulating trucking si that any company can serve any customer, let railroads do the same, i.e. Union Pacific can serve BNSF or NS customers.
And large customers, esp hazmat shippers, can run their own trains. The environmental disaster in East Palestine, Ohio likely woukd not have happened if those chemicals were self-shipped.
Railroads used to have to run their iwn passenger trains, govt formed Amtrak to take the burden off them. We could give successor railroad companies that burden back.