Just means the railroads will slow down more,
If they get a hose, knuckle or drawbar in the middle of a big city on single track it could be cut in half for quite awhile, and trains around it could end up on the hours
Especially if the Ground-based conductor is many many many miles away working on another train
Maybe Buttgig and Biten will change the rule where the engineer can leave the cab and work on the consist, or allow foamers to ride the consist for free as long as they can fix a problem
Or teach illegal migrants how to fix a problem, after all they ride freights in Mexico, Central and South America so they can do the same here, pay them minimum wage, give them a radio, food and a gallon of water and hope you don't have a problem