^^ Probably the biggest contributor to the game expanding it's reach from it's intended audience is Northernlion who was "convinced" to play it after losing a bet with his chat, fell in love with it unironically, and broke several streaming records the day it happened.
It then opened the gates for a bunch of 30-something anime hating adult men to stream it "to see what the fuss is about" or "for the lols" only to realize they just became horse racing addicts.
The I hate anime to Dancing along to the idol show after the race pipeline is real.