Earlier quoted context omitted.
> We should adopt English and move on; majority of people know it and study it. Why regress? It's extremely offensive to suggest that English is progress and other languages are a 'regression'.
I think the progress part is about having a common language, not about this common language being English. If the common language was wolof, people moving back to their own (Spanish, French, German, whatever) would be regression, as now a discussion between French, Spanish and German people would be much much harder to have.
Note that the author stealthily added a precision to his comment (which originally ended at "why regress?") since then to make clear it was about having a common language. But he has not removed the offending part.