Many of us rely on the information contained within these publications
as we planned our daily schedules. This year we even found that many
of the prices were out of date.
Chopper, a lot can change after a guidebook goes to press: information in a latest edition is largely compiled and printed over the previous year. No guidebook at all can be completely relied upon to be 100% accurate for things like hours, entry fees, security protocols, etc. Restaurants and hotels? Those can close or change management/quality in a hurry. A book's usefulness is the info that doesn't change much, like maps, suggesting walking routes, historical background, instructional "how to's", and that sort of thing.
Some guidebooks don't even print entry fees (e.g. Eyewitness Guides) as those can change so often and so quickly: they'll merely indicate that a entry fee is required.
It's always best to pull up an attraction's official website - which some books publish - or city's tourism website shortly before the trip to check for changes to prices, hours, closures for special events or renovations, coverage details (passes) etc. Also, you can report any needed guide updates to the RS staff and they'll post it here on the site: Here are some known changes for the Spain guides and the update form:
https://www.ricksteves.com/europe/spain/guidebook-updates
https://www.ricksteves.com/forms/guidebook-feedback-form
Madrid's official tourism site doesn't list the "Madrid Card" as being available for purchase, the card has no website (good indication that it's toast), and may have been discontinued late last year versus the "over a year ago" that the TI attendant told you.
https://www.esmadrid.com/en/tourist-passes