Synthwave leans heavily on a set of nostalgic elements dating from the '80's, including movies and video games from the era.
But why is there an association with Miami? In a lot of the artwork accompanying the songs on Youtube, Miami has a prevalence only exceeded seemingly by the blue-purple-yellow gradient and stylized Lamborghinis.
A selection (certainly not all) of playlists with 'Miami' in the title:
There's at least two bands with Miami in the title: Miamihighway and Miami Nights 1984.
So why would this association exist?