People around the world eat lots of carbs and have no problem with their weight. Between breakfast, lunch and dinner, French people eat about an entire baguette every day. Italians eat piles of pasta. Rice is a staple across Asia. Ethiopians have injera with most meals and Kenyans love their ugali, both are high in carbs.
The standard American diet is unique almost every other countries' diet in that we have managed to turn almost every meal from simple meals and manageable calories (corn flakes for breakfast, sandwich and an apple for lunch, "meat and three" for dinner) to massive calorie bombs of fat and sugars. When I was a little kid in the 1970s, most everyone was normal weight. If you worked at it, you could get fat. But most everyone drank soda, ate burgers and fries, ice cream, etc. and were still a normal weight. But back then, there were no Chipotle giant burritos, no Starbucks venti frappacinos with whip cream and caramel sauce and so on. American food portions got enormous and packed with sugars and fats in order to make people happy when they eat. That is because people in the US work all the time and have no time for anything else (especially if you have kids). So, food has become our sole source of pleasure. Meals are your reward for getting through your morning drudgery at work and for finish up at work and dealing with taking the kids to sports, etc. Even your morning coffee now has as much calories as people used to have for dinner. When the Standard American Diet was introduced to American Samoa, the locals almost immediately because obese. And Samoans were very found of their carbs with a lot of taro in their diets.