There was also heavy fog when Zhuge Liang borrowed arrows from his straw boat. Why is it always said that haze weather is caused by industrial pollution and agricultural pollution?

First of all, you have to understand fog and haze

The difference between fog and haze mainly lies in the moisture content: a moisture content of more than 90% is called fog, and a moisture content of less than 80% is called fog. % is called haze. The color of fog is milky white, bluish white or pure white, while haze is yellow or orange-grey; the boundary of fog is very clear. After passing the "fog area", the sky may be clear, but the boundary between haze and the surrounding environment is not obvious.