Yeah, high-fructose corn syrup comes from natural products. So does cocaine.
What they fail to mention is that corn syrup is used as a preservative for foods that would otherwise spoil easily. So you end up loading food that's already no good for you, with sugar (which is what corn syrup is), as well as bleached, ultra-processed white flour - the discovery of which allowed for foods to keep more easily on a shelf - see Hostess products. If people just ate locally grown food and lived a more organic lifestyle, we'd realize we don't need corn syrup for any reason. What was that lady pouring in the video anyway? Teach your kids to drink water and 100% natural juice.