Well, yes and no.

The premise of the book itself is to highlight that much of what was assumed about dinosaurs, depicted through those artistic representations modeled after modern reptiles, is downright wrong. E.g. newer discoveries that several dinosaur species had feathers, classifying them closer to birds than lizards (and that birds of today are more "dinosaurs" than, say, a crocodile).

Compare the depictions of Deinonychus from the 90's to today:

After the feathers discovery, newer depictions place them closer to cassowaries than lizards.

The point of the All Todays section is just to make this concept more relatable, by highlighting the fact that many distinguishing features of modern animals would be completely invisible in fossil records. The large ears and trunks of elephants would never survive fossilization, and their feet may not be interpreted as thick, fleshy pads, so they instead drew the elephant more gaunt, with short ears and a bulbous nose to explain the shape of their skull. Because the reality of an elephant might seem too outlandish for a future paleontologist to assume based on fossils alone. Certain keratinous features like horns and hooves would not survive either, so that explains the hornless rhino and toed zebra. Not to mention the most iconic feature of a zebra, the black and white stripes, would never be known, and so who would assume that's how they'd look?

And FWIW, the depictions aren't even that far off in terms of skin texture, since the elephant and rhino are already mostly furless mammals. The elephant may have too much fur, if anything. Only the zebra seems off for its lack of coat.

But the point is that it's supposed to be ridiculous, because these styles have just as much grounding as the long-held depictions of dinosaurs as scary, giant lizards. Maybe some are closer to truth than not, but the majority are just artistic license. For all we know, the tyrannosaurus rex could have been covered in rainbow feathers like a giant macaw. It might seem ridiculous and improbable, but so could the stripes of a zebra or the trunks of an elephant.