The article hinted at most of the springs legally being inaccessible. Often they are surrounded by a thin, brittle crust that can give way under a person's weight. More than the chicken could be cooked. Another issue is many of the springs have toxic minerals. There is a famous fishing hole hot spring. Before this was well known, it was popular to dunk one's fish into the spring to cook it. It turned out that the spring had a high content of something toxic, maybe arsenic. It's been at least 20 years since I visited Yellowstone, so some details of presentations are fuzzy now.