The point is that raw genius is insufficient for replicating Ramanujan-like accomplishments in the 21st century. It's almost irrelevant how brilliant someone is these days - if they haven't had the opportunity to learn a vast amount of theory, they can't really make significant progress towards theoretical problem.

The field simply has far less low hanging fruit than it did a century, or even a half-century ago. It's not reasonable to expect that a lone genius with little to no academic background in mathematics could resolve a famous open problem through sheer creativity. For literally generations the field's most intelligent researchers have spent their careers chipping away at this problem.