Chinese email addresses are not necessarily numbers. However, it is common for Chinese email providers such as QQ Mail and 163 Mail to offer email addresses that include numbers as a way to make them unique and easy to remember.
In Chinese culture, numbers have symbolic meanings and are often used in various contexts. For example, the number 8 is considered lucky because it sounds similar to the word for “prosperity” in Chinese. Similarly, the number 4 is considered unlucky because it sounds similar to the word for “death” in Chinese.
Using numbers in email addresses can make them stand out and be easily remembered by users. Additionally, many Chinese internet users prefer to use numbers in their usernames and email addresses as it is seen as more modern and unique.
So while it is not a requirement for Chinese email addresses to include numbers, it is a common practice that has developed as a result of cultural and technological influences.