I think from pre-Qin to Wei, Jin, Southern and Northern Dynasties. Poetry is more imposing when written in official script. Among the poems after the Tang and Song Dynasties, regular script is better for those who are sad in spring and autumn. Poems with different artistic conception have different effects with different fonts.
Moreover, most of the poems in the pre-Qin and Wei and Jin dynasties are four words and five words, and it looks more imposing to write them in official script. After the Tang and Song Dynasties, there were many seven-character poems, so it seems more harmonious to write them in regular script.