That’s not unclear. There’s a difference between language and dialect. The same applies to “norm”. For instance American English is different from British English due to them both being different norms. But neither is a dialect. However, within British English there are several dialects: Mancunian (Manchester), Scouse (Liverpool), Cockney (London), etc. African languages like Yoruba, for instance, had their own linguistic system made up of pronunciation patterns, grammar and syntax. This applied to the old sixteen kingdoms of Yorubaland. I just don’t think that calling an African language like Yoruba dialect does it justice. I’m not arguing your point (which was well made, I repeat) but the terminology of “dialect”. Swahili, Yoruba and Lingala are languages, not dialects. :-)

London-based, Cuban writer. Author of “Cuban, Immigrant, and Londoner” https://www.austinmacauley.com/book/cuban-immigrant-and-londoner