Su Yang changed his clothes and wore a pair of normal shoes when he got into the car.
The reason why he got changed was not because he took the meeting seriously, but because he wanted to do what a businessman should do, respect the person he was meeting.
He could wear large pants and slippers to school, but he would not go to a five-star hotel to meet a manager from a large state-owned bank. It would be an insult.
To put it bluntly, everyone had to show courtesy towards each other professionally which included workplace etiquette and culture.
For example, during important meetings, everyone would dress formally and the ladies would put on light makeup.
Although it was not a rule, if anyone did not behave accordingly, they would be deemed to be disrespectful.
Although there was slightly a restriction in freedom, there was never any freedom in the society to begin with.