The Rema was an example of a posek who ruled in accordance with the perceived needs of the Jewish communities he dealt with.
The responsa give us a vivid picture of what Jewish life was like and offer a lens into the needs of the human condition in different times and places. While one, as a matter of policy, shouldn’t drink gentile wine or get married on the Sabbath, it’s interesting to see how these poskim dealt with such scenarios.
Halakha can be flexible within the parameters of what has been codified and received from the Talmud.