What you’re saying can’t be true, I don’t claim to be any sort of expert but there are other things to consider such as diabetes. You can eat 1000 mcnuggets a day and burn it off in terms of fat, but the damage done to your body such as your cholesterol level can’t simply be burned off.
Sugar is only a risk factor for diabetes if it causes you to overeat and make you overweight. We have a plethora of data showing that there is no significant difference in many blood markers including cholesterol between a high sugar diet and a low sugar when kcalories are accounted for. Here is a meta-analysis if you want to read: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5174149/
I don't know why I can eat a whole plate piled up of chinese takeaway food and then get seconds, but if I make homemade egg fried rice or stir fry noodles I would eat less than half the takeaway amount and be full