It may help to think of things this way: Firstly, the point of a ketogenic diet is to lower our insulin and glucose levels to the point where they are no longer causing damage throughout our body. Excess stored fat is the least of the trouble they cause, though it is the most obvious.
Second, it is chronically high levels of carbohydrate intake that cause the metabolism to become inflexible. Eating a diet low in carbohydrate forces the muscle cells to re-learn how to metabolize fat, and that process takes a couple of months, but once fat-burning has been reinstituted, we can switch back and forth more easily. It’s not as though one extra Brussels sprout over the limit is going to require your muscles to re-learn fat-burning all over again.
Thirdly, everyone’s carbohydrate tolerance is different. Yours may be higher than 20 g/day (it is, however, virtually certain to be less than 200 g/day), but it’s wise to stick to the 20 g limit at the beginning, to ensure getting into ketosis. Which you have done.
Fourthly, table sugar, sucrose, has unique properties that make it particularly not a good thing to eat. Sucrose is half glucose, half fructose. The first has the same effect on insulin as any other carbohydrate. The second, however, while it doesn’t affect insulin, damages the liver when eaten in quantity. Apart from the short-term effects, fructose behaves in the body much the same way as ethyl alcohol, causing the same long-term liver damage and with the same addictive effects in the brains of the vulnerable. The prevalence of diabetes tracks very closely with the spread of refined sugar into a society. When only the rich could afford it, only the rich got diabetes. The diabetes epidemic in the U.S. began about 20 years after the soda-pop, confectionery, and ice cream industries began selling their wares.
Since a lot of us on these forums started eating ketogenically to heal or stave off metabolic disease, we are perhaps more inclined to be patient waiting for results than people here solely for the weight loss. But I put it to you that your toes and your eyesight are more valuable to you than the ability to eat potato chips and drink sodas ad libitum.