I read your response about women wearing pants as being immodest. But
shouldn’t pants be immodest for men as well, since very often, especially when sitting, the male organs protrude at the crotch? Indeed, trousers for men were a relatively modern invention originating in European culture. Previously, in all cultures, men also wore masculine style dresses that covered at least the knees if not more. I asked several rabbanim this question and all I ever received was beat-around -the bush answers.
You are vey right, and I am impressed with your feeling for tznius. “Pants” should not be tight, however not because they are not tznius, rather because they may be physically stimulating for the man..
Regarding tznius for men, there are definitely certain halachos of tznius that apply to men, such as being properly dressed when davening, or even being dressed in a dignified manner at other times. Besides, there is the hashkafa aspect of being dressed in a modest, humble manner , and also the idea that even men should dress in a way to downplay the physicality of the body, and not to accentuate it. Because after all, do we want to show that we are an animalistic body or that we are an elevated neshoma.
However there is an aspect of tznius that apples to women that doesn’t apply to men, and that is that when a man sees a part of a woman’s body uncovered it will cause unwanted thoughts, which in of itself are bad, but also he may not daven or learn when he is in such a situation. Therefore the halachos of Tznius for women are stricter because they not only affect the woman herself, but also all those around her.
S.A. E.H. Rema 23-2, S.A. O.H. 2-1, S.A. O.H. 91-1.