@Swedneck trams are generally designed to transport people, that's why lines usually go to the densest areas. And they're also a more local type of transport, so these would generally have to wait for the regular trams to leave the stops before going ahead. Or you would likely need lots of switches to allow for the cargo trams to overpass the passenger ones. Clearly not practical, although nice as a concept. For cargo, trains are the best solution.

@bestboyfriendintheworld