To a certain subset of anxious but enthusiastic middle-class Americans—for those who yearn to see Paris before they die, and want to make sure they don’t miss a croissant or fresco while they’re there—Rick Steves is a bona-fide celebrity. His voice in his popular series of guidebooks is, by his own admission, oozing with dad vibes; bad puns flow from his fingers alongside gee-golly exclamations of wonder about the majesty of marble buttresses. On his YouTube channel and in promotional materials, he tends to wear bluejeans and wire-frame spectacles and billowy button-up shirts. A Times profile labelled him as “one of the legendary PBS superdorks—right there in the pantheon with…