Certainly it's a lot less common than it used to be. There's a bigger push to find underlying causes that can be fixed, and not just say "the pilot forgot to perform a crucial step out of the several dozen crucial pre-flight items they were supposed to have committed to memory, sucks to be them" or whatever. But sometimes it really is "the pilot did a dumb and shouldn't have," especially for smaller planes with less experienced pilots.
If he was drunk, then sure, pilot error. If he was insufficiently trained, why did he think that he had a sufficient level of training for this flight? If he had too much get-there-itis, is there anything in the training that could help prevent that? Seems there is surely potential training changes relating to GPS dependence.