I mean its kinda complicated, there's so much stuff and what I said is probably wrong but
like what I understand is mobians and humans live on earth together, and coexist yet humans have their own place and mobians have their own place, humans live in the cities and houses and shit and most mobians just chill on their side with nature, or their own houses I guess
cuz if humans didn't exist then shadow cant be created so humans have to exist somewhere on the planet