The Blaue Reiter artists in Munich reacted against academic art regarding it as shallow and materialistic and chose instead to paint a spiritual attitude to nature and humanity. Their art was considered an affront to good taste, or at best the work of madmen.
The German Expressionists in Dresden and Berlin reacted against industrialization and chose to paint utopian visions of the Good Life: men and women living freely in nature. Their art was considered ugly and technically bad.
The New Objectivity artists, George Grosz and Otto Dix, having experienced the national humiliation of World War 1, reacted against the Self-Expressionists, painting technically good pictures but with ugly subject matter: corrupt capitalists and bankers in brothels
The Dadaists rejected the pleasure of beauty in art, and instead celebrated “bad” art, an aesthetic that confounded the middle classes.
Then Hitler damned the lot of them, classifying them all as Degenerates and instead promoted bad Neo-Classical kitsch.