A professor casually mentioned that when submitting abstracts to a conference in some fields in Applied Math (such as numerical PDEs), it is highly likely that they will be accepted (unless the work is garbage) - unlike some "other fields" (like computational neuroscience).
By this I understand that those "other fields" are more competitive, but I am not sure if I am interpreting this correctly. In general, how does this affect career prospects on the long run? Will it be likewise a lot harder to get an academic job in such "other fields"?
P.S. I am in a U.S. college.