If someone has Pisces for their 11th house, then a transiting Saturn in Pisces would fall within there. So the answer to your question is no, Saturn affects everyone at all times, but it in different ways.
Saturn transiting the first house will test your sense of self, appearance, and aspects of health and leadership. As it is the house of "you" and one of the angles, it can be more intense than otherwise, so doing something to mitigate it, like a Sun Square or strong AOP, is recommended.
https://satanisgod.org/www.angelfire.com/empire/serpentis666/PREDICTION-2.html
"Saturn is awful. When it hits the 1st- accidents, deaths, major setbacks, extreme hard luck. Whatever house it is in is where you are either having problems or devoting serious attention to something. When it goes retrograde is to beware of hard times coming if it is retro on the chart ruler this will also be one of the worst times in your life; lesser for personal planets. "