Are sweet potatoes baked bad for sugar sugar?

Depends on amount: It's usually ok to have sweet potato in a weight loss diet or a weight gain diet. That's because it generally does not matter if a small amount of a particular "healthy, natural food" is eaten. What matters is how much and how often, and what sort of variety there is in the overall diet. Calories matter, meaning the math always works. To lose weight, calories used must be more than calories eaten.