I think more studies are still warranted. I agreed with you before, based on that available data, but later they have found that the bmi of people who use artificial sweeteners is the same as people who don't.

2 takeaways can be considered here. First, that just keeps their palate attuned to extra sweetness, which if they just took a break for a bit from all sweetened stuff, even fruit might taste amazing again. Second, it's possible that it directly affects their microphone, perhaps feeding poorer quality microbes which would lead to all kinds of things, perhaps increasing hunger for foods those microbes like, perhaps affecting their mood, etc.

But those really amount to the same thing. If you can cut sugar, and not supplement with other added sugar, you might consume more fruits and get the associated fiber, which is probably a good thing.