Since task execution depends on tasks executing sequentially on a particular worker in some cases (e.g. PopulationTask must be preceded by GeneratorRegisterTask), it doesn't make sense to continue task execution if an error occurs.
Moreover, a task crashing may render the whole server unstable, as it leaves the server in an undefined state. This is the same kind of problem we fixed with scheduled tasks in PM3.
In versions past, pthreads was unreliable enough that random tasks would crash without an obvious reason, forcing us to accommodate this. I still don't know the origin or frequency of said issues, but I think it's time to rip the band-aid off and solve these problems for real.