No, the manufactuers do not have all the information that some modelers would like to have (for example, the first instance of a paint scheme being applied and the last car in service to carry the paint scheme).
Often times a manufacturer is working off of one photo of a car. Some artwork is prepared by people that have an interest in and some knowledge of the prototype and Model Railroading, but many are done by commecial artists that create an artwork to the best of their skill and ability who have little personal interest in the subject beyond the job.
Some art is dead accurate for the car depicted.... I make a practice of doing correct lettering for all data that I can see in photos... but some cars come through with fairly generic lettering when it gets down to the small data. The data for in-service cars and even cars when new will vary between cars (new date, repack / repaint dates and locations) but often it is not possible or practical to have dead accurate details down to the last nth for multiple roadnumbers of the same paint scheme... only the car numbers will be changed.
If someone is interested in limiting their purchases to cars that have reweigh and other data suitable for a narrow time frame, they can certainly do some modeling and restencil the cars. Maybe it should have been called Modeling Railroads instead of Model Railroading!
I would imagine that between the various on-line vendors, eBay, and other online sources one can probably come up with images of most items that have been produced. Given today's small batch production that allows for the great variety of continous new products I don't see any advantage for a manufacturer to try to maintain a encycopedia of all past products.... they are primarily interested in moving their new product into the distribution pipeline.... the wholesalers and retailers get a discount off of MSRP to move the product off of their shelves.
Where does the notion that manufacturers should provide research on their products end? Should it be required to provide a useage history of each car so that a person doesn't purchase a car that did not ever show up on the rails of the road that they model? Most manufacturers do show a reasonably sharp image (either online or in their advertisements) of the product when it is announced. I don't see any reason a manufacturer would include or post a two page brochure of fine print disclaimers similar to drugs about each car or locomotive they make....giving all sorts of reasons why a product should not be purchased by a very small segment of the market.
The internet can be used to do one's own research.... it isn't just for posting requests or the desire for it to be done by others!!! If one is going to limit their scope to a particular time range it is incumbant on that individual to do the research to figure out what that entails, not the manufacturers!
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