Why did Goethe, a famous German poet, change the style of literary creation after losing his political career?

Goethe once hated the "three unifications", so why did he trap himself now? It turned out that this was caused by the change of his thought. Goethe, a stubborn stone, could not resist the impact of feudal turbidity and became smooth. Therefore, with the rebellious spirit in Prometheus and the passion in Song of May disappearing, it is replaced by the self-liberation in Moon and the longing for heaven in Song of the Mysterious Girl. After arriving in Italy, he devoted himself to the quiet and harmonious classical art style and indulged in the ideal realm of "solemnity, simplicity, tranquility and greatness" of classical art. Therefore, in "Evy Gurney of Doris", he borrowed the ancient myth about Effini to promote the nobility of reason and the power of humanism. Tasso, on the other hand, expressed Goethe's anguish that he had to compromise with reality through the dispute between Tasso, a court poet in the Renaissance, and his ministers. Such artistic content inevitably requires strict classical art forms. In this way, the spirit of sturm und drang in Goethe's youth, after ten years in Italian politics, finally transited to classicism with the theory of human nature as the highest ideal. The classical period of German literature also dates from 1786 when Goethe came to Italy.