I would say follow the money, create a product or service that generates recurrent income and channel that income to study the fundamental problems that would interest you. Owning a product or platform opens up for a lot of opportunities.
Also, even with a steady income, not having access to academia can get in the way of successfully advancing research.
Still, I do agree that it's a great option to buy yourself some freedom, if you are capable of doing so.
This way of getting access to academia is based on the premise that you already did quite some research - which is much harder if you don't have access to academia. :-(
> Thankfully research is not guided by notions like "what makes money in the current economy"
That's right, it's guided by "what gets grant money in the current paradigm"