I have to say that the openness of Tang culture is still quite high. If you had dared to write these innuendo poems in the Qing Dynasty, you would have been dragged out long ago, but nothing happened in the Tang Dynasty. For example, Meng Haoran once wrote a poem satirizing Xuanzong of the Tang Dynasty. After reading Meng Haoran's satirical poems, Tang Xuanzong flew into a rage, but it doesn't matter. He just said you didn't want a career and blamed me for not giving you a chance.
Meng Haoran was not convicted for this. After that, he went to live happily. Even Meng Haoran's straightforward satire is no problem, and Bai Juyi's poems are naturally no problem.
Of course, one more thing, I don't think Bai Juyi's Song of Eternal Sorrow is a negative evaluation of Tang Xuanzong. Isn't it an alternative appreciation? He said that Tang Xuanzong was much better to Yang Guifei, which was not negative. Some people may think that he is saying that Tang Xuanzong is addicted to beauty and so on in this way, but I don't think there is any problem.
Also, I feel that Bai Juyi's Song of Eternal Sorrow always makes people feel that he is praising Tang Xuanzong and Yang Guifei. I've been thinking, is it because he was touched by their love when he was writing, so the style of writing turned sharply and became a love story?