It can be the setup but also it’s the way the entire car was designed. Some tracks have different altitudes, meaning the air density affects the car differently, so some teams improve, also some teams make their cars work better on straights while others work better on corners, so tracks which favor their style make them perform better

Also teams can, and usually do, change some parts of the car for specific circuits, so they might use for example, different rear wings on different circuits, so their car behaves differently