Her path to JAV was legendary lore by JAV standard (the average performer came out of nowhere and disappear into nowhere within a year). But no I don't think it works like "oh I heard of her from J-pop and wow now can see her naked and sucking dicks!" Because Japan's definition of celebrity is so board and threshold for pseudo-moral-outrage is so low that it's impossible to know all celebs and outraged by the daily scandals.
Typically you first hear of this person when there's a celeb-turned-JAV from the announcement/news/rumor of her JAV debut. You have to rely on the debut itself to inform you that "she's a lit celeb, trust me!" But to me, a washed-out backup dancer of a pretend-J-pop group (sorry if I insulted SKE48 fandom here) isn't really worth a lot of attention.
So yes she has a very pretty (surgically enhanced) face, a very nice figure (assumed to be augmented) and lit (by special generosity) celeb creds. But these advantages are not super rare. These only launched her career not made it. Other girls with such advantage typically leave the industry after 1-2 years. Especially the celeb-to-JAV sensational boost can fade away in as little as three months. Her debut was ingeniously and meticulously engineered to both milk the sensation boost and elevate herself to sustainable JAV stardom.
I believe at least two other JAV performer tried to replicate Yua Mikami's JAV launch: UNPAI うんぱい and Asumi Mirai 明日見未来.
She is not just retiring on her own terms, she's making it an epic spectacle, maybe as part of marketing strag to boost her social media empire. I'm pretty convinced she had an affair with NEWS (a much more legit J-pop boy band) band member was a career move. So it's possible to speculate this grand retirement is also a boost to promote her next career move.
