Tbh prescriptivism has its place in official over regional communication and language learning. We wouldn't understand each other if we were writing each in their local dialect and when you start learning a language, you don't want to first need an overview of the dialect continuum.

That said, in unofficial writing it doesn't matter as long as you write intelligible and advanced language learners should learn about varieties. I for example was tought British English at the start and in the 4th year, we learned about American English and the differences to British English.