What harm does duck sitting posture have to knees?

A very twisted posture, China people didn't have this problem before, at least my classmate didn't have it when he was a child. Now most of them are from Japanese anime and island movies, right? What's more abnormal is that even boys are learning this sitting posture, which is really speechless. This kind of sitting posture will cause the pressure imbalance of hip joint, knee joint and ankle joint, which is easy to cause injury. The knee joint is opened outward to the maximum, and the heel is close to the hip, which causes great pressure on the cruciate ligament and collateral ligament of the knee joint and bears the weight. In the case of extremely unbalanced joints, long-term self-weight compression will definitely cause problems, as well as ankle joints and hip joints. If it is not good to just sit for too long, that kind of pain, because it is static pressure, should not be too serious. Maybe it's just a muscle strain, or ligament damage at most. But I personally guess that people with general posture problems can't be just a posture mistake, but a comprehensive problem caused by most mistakes and bad postures. If the subjects sit still for a long time, the hip joint, knee joint and ankle joint will be deformed to varying degrees, and standing, walking, running and jumping can all be normal discomfort, pain and injury. Learn the correct posture, exercise muscle ability and completely change yourself. Go to the hospital first to see if there is any effusion. Determine the location and severity of the injury. Have a stool, don't kneel, sit and squat with straight joints, which requires training and learning, don't pretend to be cute, learn animation. He can draw whatever he wants. Why do you have to learn? I feel that the duck's waist and ass can be more comfortable when sitting. I also feel that it is muscle and joint problems caused by sitting for a long time.