I disagree, it's hardly impossible. I would say any reasonably gifted maths grad student who has chosen the right combination of subjects (the requisite math, s

I disagree, it's hardly impossible. I would say any reasonably gifted maths grad student who has chosen the right combination of subjects (the requisite math, some cryptography, along with a low-level programming course or two), would be able to start working on attacks on EC systems. Do those people grow on trees? No, because it's a much less common specialisation than most others (like aiming for the financials industry, or statistics/analytics/big data) simply because of the number of paying jobs in each field.