I don't disagree with the conclusion of the pubmed article. People who eat fresh fruit may have had better outcomes. However, are there other confounding variables?
For instance, maybe those who ate fruit chose to eat healthier overall, lost weight, and hence had less insulin resistance due to weight loss, leading to better glucose levels. There is for sure a correlation here, but a correlation does not necessarily mean it's a causation.
Eating fruits especially lower sugar fruits like cantaloupe are fine. Drinking the juice of fruit does not have the "fiber" and will lead to faster sugar spikes. When I think of diabetic complications, I think less about blood sugar spikes and more about average blood sugar over three months because there is much more data we can relate to that in relation to complications.
As far as the Type I diabetic....I am Type I myself. We make no insulin so we have to take insulin. Theoretically we can eat anything we want as long as we know how to count the exact carbohydrates in relation to the amount of insulin we need. So a Type I diabetic can eat sugar and still be in perfect control.
When I say limit fruit, I mean a Type II diabetic who does not take insulin. If I have a patient come in who is eating lots of sugary fuits...AND is losing weight, then I will not tell them to stop. Weight loss is the most important; if fruit makes them eat less calories, then great!
Again, I am not looking at spikes in sugar; I am looking at the overall average blood sugar, which we can relate directly to complications.
If you're not talking about blood sugar spikes I'd say there's even more of a reason for people to eat fruit as fruit is extremely low in fat (aside from avocados, etc) because lower fat means better insulin levels (type 2) in general as insulin resistance is almost entirely determined by fat in the bloodstream blocking glucose from entering cells.
Juice, yeah, that's horrible for diabetics, even if you're doing lots of exercise it's just a disaster.
https://www.ncbi.nlm.nih.gov/pubmed/15650564
If not fruit what could a diabetic possibly eat in it's place? There's no better carb in general other than potentially sweet potatoes, and it's unadvisible to have any more fat than absolutely necessary, and lean protein is rare to find unless it's in plant-sources as well is generally not beneficial to ones overall health in excess. Furthermore protein also requires insulin to metabolize, thus increasing insulin needed and thus insulin resistance.
I would disagree with some of your discussion on protein. While insulin is involved in protein metabolism, it does not elevate blood sugar. If you give a Type I diabetic a steak with no short-acting insulin, you will not see much increase in their blood sugar.
Furthermore, you talk about resistance. Resistance has everything to do with fat...as in excess weight in an individual...however, if a skinny individual eats fat it is not like that specific fat is floating around the bloodstream causing insulin resistance.
High fat foods should be discouraged because of its potential for weight gain. Sugar will eventually lead to more fat storage as well.
https://www.ncbi.nlm.nih.gov/pubmed/9416027
My recommendations: Eat the meals that are lower in carbs and eat protein that is lower in fat. If you do this, you will decrease your overall calories, lose weight, and have less insulin resistance.