It is true that toy train manufacturers modelled their products after the real thing. This includes Lionel, Am Flyer, Ives and yes, even Marx.
When I was writing for Classic Toy Trains magazine in the late 1980's and early 90's I did an article called "Marx Trains True to Scale" I had noticed that Marx Litho trains copied distinguishing characteristics of the prototype. Good examples of this are the Southern Pacific #6000 diesels. Also many other examples.
The toy manufacturers' early production of steam locos were a bit more loose with "artist's license", but the electrics by the big 3 companies were close to the real thing, as the article you posted pointed out. Lionel, AF and Marx all quickly manufactured examples of the M-10000, M-10005, Flying Yankees, CBQ Zephyrs etc when these trains were introduced to the public, all about 1934. They saw the value in imitating the modern streamliners. Even Hafner had somewhat-realistic streamliners in the 1930's. Lionel got drawings from GM / EMD when they produced the F3's and NW-2 switchers in the late 1940's.