It's been sixteen years, and the real heiress has finally been found by the rich family and returned to the Zhus. Everyone thought that this girl who grew up in the countryside must be crude and embarrassing, and the entire circle of wealthy families was waiting to laugh at her.
However, on the day the real heiress arrived, she broke everyone's expectations. As for why she did that, let's go back to the scene when Ming Jing first appeared on the show.
A beauty like a flower that blooms beyond the clouds.
Everyone understood - Ming Jing was the real heiress in the story.
As a standalone story, it was pretty dramatic. But if Ming Jing was the true heir in the story...
All that was left was sympathy.
The fake heiress was enjoying the wealth and luxury of a rich family while the real one experienced hardships growing up in the countryside. Her various actions in the show now had a reasonable explanation.