In case of zombie apocalypse, your best friends will probably be a bicycle (to get away from the zombies in almost any terrain and road condition, not be without industrial fuel the next day, and be able to do needed repairs with rough tools and scraps that can be found), a hunting knife, and maybe a crossbow if you can find one (weapons that can be sharpened and reused, and crossbow allowing random joes to just make piercing sticks (again with scraps that can be found anywhere) that work like an arrow, again weapons that do not depend on industrial infrastructure that will not be available anymore). Games that need electricity would be extremely hard to use, it’s better to buy card decks that have multiple rule sets for different games to play, like french decks and tarot, maybe a tabletop set that also has multiple games.
Germany took ~150 years of Lebensreform movements (which itself had Freikörperkultur as one line of thought and action among many) to get there. As the articles mention, things that contributed a lot included the fact that they still had living traditions of public bathing in sparsely populated areas (add Scandinavia and rural areas to the mix), and that Germany was a very industrial and educated country, that had the infrastructure to generate what were essentially academics in academical circles theorizing and practicing all of these ideas first, and there was still a strong memory of pre-industrial life in general (that these movements saw as better in those lines of way of life, to react to the then novelties of industrial and urban living). How would we translate that german social environment to places and societies a lot different ? example, much poorer with less intelligentsia, no prestige or memory of premodern living, multicultural multiethnic societies with low cohesion, with outright hostility to all these nature-weirdos that want veganism, nakedness, primitivism, etc while the current media landscape is dominated by hollywood idolizing private wealth, luxury and puritanism (like the amount of sex in Marvel films, after Iron Man 1).