//And why does China need English. In fact I know why but wondering if a Chinese person will ever admit the truth about this.//

Another point. The US uses English, the language was created in the UK. Brazil speak Portuguese, language created in Portugal. South America speaks Spanish, a language created in Spain. If you want to be relevant because your country created a language being used by others countries, it does not mean much anymore.

Another sample if you have a computer, Microsoft created the operating system windows, still the most popular in the world. Lots of software companies use Windows OP to run their apps, now some of this companies are bigger and more successful than Microsoft.

China made paper first as an invention, countries all over the world use paper for money currency and a bunch of things. This and other great inventions did not saved China for extreme poverty and Chinese workers being slave overseas working for almost nothing

Of course relevance or irrelevance can change if your country re-start a new golden era where citizens like you will not be traveling to teach English as a job,instead you will be traveling as a tourist spending lots of cash anywhere you go.
Probaby a better point for you is that the best movies and music stll in English. All the best.