Aya Miyazaki retired...???

Lol, maybe for 10% of all the youtubers across the world. I know that even with 1 million subscribers, video ads are enough to make money (depending of the channel content).
 
She always seemed interested in music so I hope that she will have at least moderate success as an artist.

Too bad it's mostly likely not gonna happen. She's only relevant because of AV and it's not like she was a super big name. And breaking into the mainstream will be hard because celebrities are often seen in black or white, especially female celebs. You can turn a virgin into a whore but not a whore into a virgin.