Mass parties provided a unifying heuristic that hyperpolitical individuals now lack

Evidence

By promoting a worldview, political parties helped their members make sense of the world. Opinions were filtered, at times in openly authoritarian ways. Party discipline went hand in hand with intellectual discipline: through ideological training, parties imposed a shared outlook that allowed workers to grasp abstract social processes as amenable to transformation. By contrast, ideological disorientation is a hallmark of the hyperpolitical age. Debate erupts over one issue today, another tomorrow. But individuals no longer possess a heuristic capable of unifying and imposing coherence on their various viewpoints. What emerges instead are fleeting, episodic partis pris. — Anton Jäger, Hyperpolitics, 122