If the indie writers who made a lot of money in 2012-2014 had followed this advice, they’d still be writing and publishing. Sure, their incomes would still be down, along with their sales, but their careers would continue.
What happened to these writers?
Well, they will say that their sales went down to unsustainable levels. Those writers will say there’s no point in continuing now that they can’t make the same kind of money they made in 2013. Those writers will say that writing, as a profession, is impossible.
And it is, if you don’t understand money management.