Let's first reconstruct the strongest argument of this view: it is true that fiction can initiate a fascination for a destination, and that travel guides then become practical tools to realize this desire, like planning a trip inspired by a novel about Patagonia.
However, reducing guides to a simple "component" of inspiration born from fiction neglects their ability to generate autonomous and direct inspiration.
A guide can spark the desire to travel through its concrete descriptions and images, long before a work of fiction enriches this idea.
For example, a friend decided to visit Galicia after flipping through a Routard that detailed coastal routes and local gastronomy, without any story pushing him there.