How far apart do you imagine each world within Sims 4 to be from each other?

I think the two basegame neighborhoods are like Florida and Arizona in the US. I think of Windenburg as being Europe and San Myshuno as an Asian metropolis. I feel Brindleton Bay might be British, because GB is known to be especially fond of animals :)

So to answer the OP's question: Within driving and/or flight distance.