Most folks with the degree and certification required to teach can find another full-time job that offers benefits, e.g. health insurance (which even a million dollars will get burned up quickly if a serious medical issue arises and you have no insurance).
But I think the point you’re missing is that she can continue making shit loads of money on OF for as long as she can while also working another job, as OF isn’t exactly something you need to 8 hours a day to do (though, some models probably do when you factor in advertising and getting your name/rep established).