I know several full time independent miners that do quite well. They aren't living in the dirt or scrabbling for a living.
They do have skills that they have developed over time like any other profession. A successful independent miner has to be a geologist, mineralogist, chemist, heavy equipment operator, hydrologist, accountant, welder, surveyor, machinist and inventor. It's hard to imagine a job with a greater skill set than a successful independent miner has.
It would be difficult for a retirement age person to become a self sustaining miner without already possessing most of these skills along with very good health. It does happen that a person of any age or skill set finds a good deposit and mines it to the best of their ability and at a profit. A full timer will have several such deposits lined up so they can continue working, at a profit, after mining their present deposit. That is the basic difference between the successful adventurer and a full time miner.
This is a gold prospecting forum but I think it needs to be said that most of the wealth to be found in mining does not come from gold mining. Most of the successful full time miners I know are open to any mineral deposit that is of the scale and quality they can profitably work. A decent perlite deposit can be just as profitable, and may be easier to work, than a placer gold deposit. For the full timer it's all about the money.
I do know a few independent miners who have succeeded while only prospecting for gold. It's a specialty that can be successful just as tin miners may only ever mine tin. Being specialized just cuts down on your possibilities it doesn't guarantee failure. I know a man in his early thirties with wife, children and home who has been quite successful just mining placer gold. He works very hard, entirely alone, and grew up in a gold mining family working known deposits since he was a child. There are those acquired skills again. A common theme in the successful miner's story.
That brings up the subject of partners. A tricky subject. A partner can fill in some empty spots in your knowledge, skills, equipment or money. That can be very good.
If you have the skills and knowledge to go it alone you might be better off doing so. Gold does funny things to people, it's a proven fact. I think partners have ruined more potentially successful small mining ventures than equipment problems or government over regulation ever has. If you do find a partner that compliments your skill sets and needs, shows up for work, has decent hygene and doesn't go crazy when the poke gets full you should probably hang on to them no matter what. They are one in a million. Nuff said about that.
There are opportunities for new prospectors to go full time. It happens and when it does you get wonderful stories like the one from born-to-mine. Sometimes it really is about seizing the opportunity when the time is ripe. born-to-mine's 14.67 ounces isn't going to cut it for a season's take for my friend with a family and a home to support but it's probably more than enough to keep a retiree with time on their hands mining for years to come.
If you have the desire and drive to go full time you are half way there but don't ignore the skills and health requirements needed for a successful mining venture. And be assured that there are others out there succeeding and prospering as small miners - it's not just a pipe dream.
Heavy Pans