The difficulty with proving bleeding edge results in mathematics is normally not that the question is particularly advanced or difficult to understand, but rather that if it had an easy solution, then it would likely have been solved by now.
The only times I can think of where this is not the case is after a major, yet easy to understand, discovery makes a lot of formerly hard problem easy, or a field of mathematics that is either young enough, or uninteresting enough that it has not yet had significant time devoted to it.
The only times I can think of where this is not the case is after a major, yet easy to understand, discovery makes a lot of formerly hard problem easy, or a field of mathematics that is either young enough, or uninteresting enough that it has not yet had significant time devoted to it.