I think you’re right but it will probably happen in Canada first because of the protectionism for US sugar growers; the price of sugar in the USA is ~4x what we pay here, which is why most American soda producers switched to corn syrup in the first place.
Funny, the last time I was on deployment overseas (2007) our aircraft carrier received stores from various Arab countries. We'd get cases and cases of Arabic soda, American brands such as Coke, Pepsi, Mt. Dew, Dr. Pepper, etc. all familiar logos except they were written in Arabic. The younger sailors would complain that the sodas tasted funny. I told them "this is how they're supposed to taste!" as they were all sweetened with sugar. It seems that outside the United States (and, I guess Canada) sugar is still the primary commercial sweetener.
Oh, and Arabs drink Orange Fanta like it's water. I've never seen more Fanta in my life than I did in Arabia.