I am allergic to the shiny side of traditional travel guides when it comes to destination choices.
Honestly, what is the real behavior change or cash flow for most people today when choosing their trip?
The internet offers much more current and free information, making the physical guide a niche supplement, not an essential element for the initial decision.
Ask any modern German traveler if they buy a guide to decide where to go; the answer will probably be a laugh, except for very specific situations like lack of network in the wild.