BTW, as another poster noted, AC is working on it. So is NARP (National Association of Railroad Passengers), ESPA (Empire State Passenger Association), NYBC (NY Bicycling Coalition), NYS DOT and many others. I'm sure other cycling organizations are on it elsewhere.
As mentioned, the baggage cars are ancient, made in the 1950s. New ones are being produced, and they do have accommodation for unboxed bikes. Some of the new passenger cars will too, these replace coaches that are almost as ancient (70s-80s).