Just because you didn't like something doesn't mean other people don't. Adults who didn't grow up eating Hershey's chocolate frequently don't like it due to a compound that they use to preserve it that tastes kinda like vomit. What you like is influenced by society and what you grew up eating.

Like other commenters have said, sour candies have always existed in some capacity (before Lemonheads it was likely candied fruit including lemons and limes), and back in the 90s Warheads were super popular due to the edgy marketing and the "kids doing foolish shit" factor. I'm part of the generation that grew up with Warheads being popular and I once kinda gave myself a chemical burn by sticking way too many in my mouth at the same time. Sour Patch Kids are one of my favorite candies now as an adult. And guess who the parents of the kids today are? Yup, the same people who ate the entire package of Warheads in one mouthful in a dare.