Einstein may have been ‘unemployed’ in his chosen field but he was never an amateur.
An amateur is someone who engages in an art, science, or athletic activity as a pastime rather than a profession. When Einstein wrote his first paper on special relativity, he was indeed an amateur. But it took an amateur to explain the constant speed of light that professional physicists failed to account for.
Through the centuries, many amateurs have made important contributions to science and mathematics. Do not discount the amateur. Just because a person is not receiving payment for some research does not mean necessarily that that research is invalid.