I'll only chime in to say that the idea of when someone "joined social media" being an indicator for their language is a bit over simplistic, and won't hold up

I'll only chime in to say that the idea of when someone "joined social media" being an indicator for their language is a bit over simplistic, and won't hold up as a model over the test of time. Social circles and the development of culture is not a fixed thing. Nature vs nurture, and the rest.