I'd venture to suggest that this can be a problem in any cutting edge field. For example, look at computational complexity. Resolving questions like P ? = NP are tough. There are many different proposed methods of attack and lots of people saying that methods that other people are working on don't stand a chance or are extremely unlikely to succeed. So even in fields that are not young and are not interdisciplinary this sort of problem can exist. This difficulty may be a natural corollary of simply doing research on the cutting edge of a field. The only reason this might seem more prominent in young fields is that, if I may abuse a metaphor, in those fields there's a much larger surface area that is the cutting edge.