that this is not the important question. Underwear should be made of cotton, which is breathable and absorbs sweat. It is better to wear it comfortably. Also be careful not to be too tight, it will make the scrotum close to the crotch and raise the temperature of the testis, which is not conducive to sperm production, but you don't have to worry too much. Once cancelled, it can be resumed. Breathing and absorbing sweat is more troublesome. There is no essential difference between thrift and hygiene, triangle and right angle, except personal hobbies and comfort.