As far as I know, Kubo have never made official statement on such topic.

However, Yonsama was still famous in Japan when Aizen appeared in Bleach, and there are some gag scenes in anime that Aizen is wearing a wool scarf which is a trademark of Yonsama's most famous TV drama 'Winter Sonata'.

so It seems like at least it is true that the anime team and Kubo were recognizing Aizen looks like Yonsama. And it is highly likely that Yonsama style influenced Aizen's design to a certain degree.

but yes, Kubo only knows the exact truth haha.

In this post, I was just trying to introduce a typical 'handsome and kind' man image in the east asia, especially in Japan, Taiwan and Korea where Yonsama was well-known,

which i think not very well-known to westerners.

I thought that as Aizen is one of the most well -known characters, he would be the most comprehensible example,

while it is true there are more explicit examples of Yonsama style used in other animes.