How big would a niche have to be to be a "success"? Even if it targeted only fringe libertarians, there'd be enough of those on the world to keep it alive.
A niche would be a "success", but by definition not "huge".
My business targets investors outside the mainstream Wall Street advice. Many would even call themselves "fringe libertarians", including a lot of the people I work with. The guy I share office space with even calls himself an anarchist - basically a libertarian under his definition.
Anyway, it's a very successful niche. But we'll probably never have more than a few thousand customers worldwide.
Some of the stuff circulating about bitcoin seems to point to it replacing all fiat currency and taking over the monetary world. I've learnt quickly that I should ignore that and focus on more realistic aspirations.