Food Scientists Are Getting Fed Up with Picky Eaters

That's not the argument, though. The argument is that we've been genetically modifying our food since the dawn of civilization via selective breeding, to the point where there's no such practical thing as non-GMO food, rendering the anti-GMO efforts fruitless (pun intended).

The actual issue with this argument is that there's a pretty big difference between selective breeding (which is leveraging a natural process to artificially encourage or suppress phenotypes) and modern-day genetic modification with more precise gene editing (e.g. with CRISPR or somesuch); the kind of genetic modification being done today is very different from the kind of genetic modification we've been doing for millennia. I guess that's similar to nuclear reactors (natural or otherwise) being very different from nuclear warheads, but the argument ain't about it being natural; it's about it being normal (gene editing ain't quite normal yet) or safe (as far as I know it is, but I'm no expert on the subject).

On that note, unless you're out in the wilderness foraging for nuts and berries, the food you eat is almost certainly not "natural" in a strict sense; even without selective breeding, the very concept of agriculture is quite far removed from nature (and I'd argue that selective breeding is a dependency of at least modern agriculture, and probably agriculture in general, prehistoric included).