The Agta people of Luzon in the Phillipines were often captured by the fierce Sambal people and then sold as slaves to China and Borneo, and that was the end of their hunting and gathering. Unless a society is organized in such a fashion that it can defend itself, it will suffer the depredations of societies who are better organized. See the complete takeover of the Western Hemisphere by Europeans for thousands and thousands of other examples of that. The big advantage that Europeans had over the Native Americans wasn't weaponry, since the Indians soon became more proficient with firearms and metal edged weapons than the Europeans, and the warriors were also simply better fighters and more physically fit. But the Europeans had writing, and writing allowed them to commit people to contracts, create orginizational plans, communicate accurately over long distances, make maps and charts, and create written laws and treaties which of course the Natives were absolutely clueless about. Typically on a military campaign, Native warriors started slipping away if they had acquired booty and captives, or if the possibility for victory seemed questionable. There was no authority capable of making them stay on the warpath until the Europeans were defeated. On the other hand, European soldiers or militia had to stick out the whole campaign until the Indians were destroyed or driven away because they had made their mark on a contract. Going home without permission would cause them to hanged from the nearest tree.

For hunter gatherer societies to exist, they have to be far away from other better organized people that would take advantage of them, and with over 8 billion people on the planet those days are over.