I spent quite a bit of time confused about this topic, and honestly I still get confused when I try to read the actual definitions. But one video that was really helpful for me is this one: https://www.youtube.com/watch?v=UsOv0DcXk6w&ab_channel=Physiotutors Hopefully links are allowed to be posted here.
After that, it was easier for me to understand why sensitivity was preferred for screening tools.
Another way to think about it is remembering how COVID tests work: If you get a positive, you definitely have it; if you get a negative, it’s not as conclusive that you don’t have COVID. COVID tests are sensitive, and not as specific.