Why is the evaluation of poetry creation in public security schools not high?

The literary theory of the Gong 'an School has always been highly valued, but people don't think highly of its poetry creation. There is something worth analyzing here. China's classical poetry has a long history, until the Ming Dynasty, with remarkable achievements. However, it has also formed certain routines in terms of format, artistic conception, image and vocabulary, and it is difficult to make a big breakthrough and be compatible with the active, exposed and popular life feelings formed in the society in the middle and late Ming Dynasty.