I feel that Guangshan County, Xinxian County of Xinyang City, Henan Province and Qichun County of Huanggang City, Hubei Province have similar accents. Why?

I am from Qichun, and I have friends in Xinyang. Their accents are somewhat the same, but not exactly the same.

I don't know why. I think maybe friends can communicate in their hometown dialect after spending a long time together. I have been with people in many places for a long time and can communicate in my hometown dialect.