How does WeChat reject each other's information without hacking it?

Wechat rejects that the other party's information is not black as follows:

Tools: iPhone 13

System: iOS 13

Software: wechat v8.0

1. Enter the chat interface of the contact to be blocked, and click the three points in the upper right corner.

2. After entering the main page of chat information, as shown in the figure, we click on the message to avoid disturbing.

3. When the button here turns green, it means that the Do Not Disturb message has been turned on, which can block this person's message.

4. If we blacked out the other party, when the other party sends you a message, it will prompt "The message was sent, but it was rejected by the other party" and add a red exclamation mark.