Diet sodas are safe. Since the yeast can't digest artificial sweeteners, you prime them with just enough regular sugar to carbonate at room temperature. Regular soda, natural carbonation and glass are a problem, because the yeast will continue working until the bottles explode, unless the soda is kept cold all the time.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk