I mean, people would obviously propose English to be the world language, but its problematic since that is like telling the world that British Imperialism is somehow “okay”, which is not okay.
So we need another language.
But how could we possibly agree on one?
Do we just find the 100 rarest languages then use one of those?
Do we create a new one?
There were hundreds of attemps in the 20th century. You should learn the history of Esperanto to know why it can’t happen. That was the closest we ever got to a global second language.