She may feel she's too old for it now, it's what everyone is expecting so she won't do it out of defiance, it'll ruin her chances of finding a man even more, it'll give more fuel to the haters, justify the reasons her ex left her, she's already seen as the poster child of gold digging and being a hoe which got her a lot of hate, and starting one will only further cement those titles.
Honestly those are some very good points, not to mention the fact that she has a son and delving into OF could definitely have negative repercussions on him when he gets older if the OF or Fansly blew up in popularity.