At this point I think it almost definitely is "most" in USA at least, going by volume/count/shelf-space.

Like >90% of energy drinks use at least one (normal red bull is a rare exception), and diet sodas typically have more shelf space than regular from what I see, often by a huge margin.

Almost all gatorade-likes have it now too (I typically can't find even a single counter-example in a store, unless they're one of the oddballs carrying regular gatorade (most do not)), often also including regular sugars. Even stuff you'd hope would be maximally-simple like pedialyte has it in almost every variety.

Almost literally every single water-flavoring in stores uses them, I go years without seeing unsweetened or sugar only. skratchlabs.com is sometimes in expensive bike or running stores though, yay.

Stuff like Liquid Death used to be just low amounts of sugar, but now has stevia in it too. The same happened with Bragg's drinking vinegar(???!).

It's wild to be someone who dislikes the flavor of these things and read labels, and watch the massive rise in use in despair. They're in lots of candy bars now too! That was a rather nasty discovery.