The arguments against artificial sweeteners seem a little like the arguments against e-cigarettes. Yes, there are plausible mechanisms by which the substitutes may cause harm. Yes, further research is needed. Yes, cutting out both the original and the substitute would be better.

But people really like (or "like") sugar and cigarettes, so the most likely outcome of loudly proclaiming the dangers of substitutes is that more people stay with the originals, which are almost certainly worse.