The cleaner and more mild looking cars (and better looking) are more of a shakotan style, just low and clean, usually still with stock panels and slightly rolled fenders/flush wheels/air dams and the occasional oil cooler. I prefer my cars being clean personally, over the fop clutter just ruins cars for me
bosozoku cars are over the top and deliberately made to make people say "what the f*ck" as a form of rebellion. Bosozoku means "violent running tribe", and wasn't a specific gang but was a phrase made to describe any group of people or gang that fit into the over-the-top scooter genre. Not my cup of tea, but that's how car trends get started, rebellion and such.
Bosozoku is also a dress style in japan too, I dont know if you have seen yuyu hakusho but kuabara in that show fits into this category. Jump suits and trench goats, and tall or slicked back hair.
'70 sl350, '86 spree, '88 cressida