That’s not german culture, as in german philosophers or literature, but rather how to live, “fir zich” in whatever society we live in. Nowehere in “maintaining the social order” would we include learning Immanuel kant or nietzsche. He’d say to consult an expert in german etiquette. Happens to be that burping in public is a flattering gesture in Germany; it shows the host that you arr satisfied with the meal; those things change and are of no intrinsic value.
He was also living in a time when modesty, fairness and real justice were championed; american culture with its many immoralities, its love of gender benders, toevos and “pride” would be shunned by any ehrlich jew, especially someone like rav hirsch. Rav hirsch would not want one to be in any way engaged in sodom ve’amorah.