I'm intentionally ignoring all the T vs F function fluff from this thread and post, which is important too, just so I'll know the initial question so I can answer. So... *ignore* we aren't evil, you know.
Whether or not the NFs have fulfilled their causes. Depends on NF and their causes, depends how they are attempting to reach it. It's all subjective. Most NFs lack a plan, we just feel our way through life and what is meaningful. Easy to understand, no?
Besides all in all making mistakes and sometimes crewing things up is only humane. We aren't perfect, what even is?