But it looks like the secret of the author is: just work in academia.

Much better career advise I've heard is: What kind you shit are you much better at suffering than other people around you seem to be?

It is not a simple task to identify parts of the code where user-controlled data enters the system (so-called ‘sources’ in taint analysis nomenclature), and it is especially hard to find all feasible paths from these to the security sensitive ‘sinks’.