I am still waiting for anybody to provide a clear source that tightness anywhere is a real halachic problem.
it is included in the Halachah that a woman must be tznius, which includes all sorts of behaviors that one must use your Daas Torah to determine.
why do you need a written source for particular detail of tznius?
do you have a source for why six-inch high heels are not tznius?
you know what tznius is
you know why skin-tight clothing in a woman is not tznius
im not about to state it here.
your insistence on a source is as silly as could be.
only in todays immoral degenerate climate could you ask such a question
lok in Rabbi Falks book if you wish a source.