Why does the perpendicular to the line connecting the crescent horns often seem not to pass through the Sun?

Because a straight line in space connecting the crescent moon and the sun, projected onto the celestial sphere, is an arc of a great circle.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.