[int_19h]

For the most part, sanctions are designed to be "something" in the infamous "SOMEBODY DO SOMETHING RIGHT NOW!!!1!" mantra. They rarely achieve any of the goals that you enumerate, disproportionately inconveniencing regular citizens - government actors have the means and the know-how to work around them. But mob justice demands an eye for an eye, which is to say, someone must be made to suffer - and sanctions provide a way to do that, even if the people actually suffering are rarely morally responsible.