You were never going to keep this girl relatively small. She is way too pretty and hot and most importantly she has a gimmick. That thick accent and her Appalachian/Hillbilly stuff gave her something different to set her apart from other hot girls. She was always going to blow up at some point when more dudes discovered her. She also does comedy content on Tiktok which brings in people. If she could ever do YouTube and YouTube shorts she would really blow up.
I don't think she will pull back even though she is going to get a lot more buyers. That is due to the Slippery Slope of Onlyfans theory. Once you start showing more it's very hard to pull back and reverse course. The Slippery Slope of Onlyfans states that once you start on Onlyfans, guys will start pressuring you to show a little areola and tease nipple. So eventually you start to show a little areola and tease nipple and that is the stage she is at right now. Then they will want you to do your first blowjob content sucking lollipops and then dildos. So you do that. Then it's free the nipples. Eventually you free the nipples. Then they will want bottomless. So you do bottomless. They they will want open legs and vag. So you do that. Then comes masturbation, girl/girl, boy/girl and so on.
Guys will always demand more and either you keep progressing or you have to get off the Onlyfans train. In her case Fansly train. She seems to really like being on that train so don't expect her to get off anytime soon.