We can now treat a lot of conditions we couldn't before. People used to die all the time of infections or any number of other conditions we now consider fully curable. Medicine as we know it is a relatively young science compared to physics or mathematics for example. We can treat most bacterial infections. We can manage most virus infections. We can perform life-saving, high-precision surgeries. We couldn't do any of these things just 100 years ago — that's nothing on a historical timescale.
Thing is, medicine/biology is a unique field because it relies quite a lot on advancements in other fields for its tools. You couldn't research cells before microscope was invented. You can't begin figuring out what each part of a genome does before you've sequenced it. You can't begin to research functions of specific proteins before you've solved their structures and got the ability to manipulate their production and/or attach markers to them. And so on, and so forth. Not so long ago the main approach in medical research was basically "try stuff randomly on lab animals and see what has a beneficial effect". Now that we can peek into the internal workings of biological systems we can use a more direct, more engineering-like approach.
Thing is, medicine/biology is a unique field because it relies quite a lot on advancements in other fields for its tools. You couldn't research cells before microscope was invented. You can't begin figuring out what each part of a genome does before you've sequenced it. You can't begin to research functions of specific proteins before you've solved their structures and got the ability to manipulate their production and/or attach markers to them. And so on, and so forth. Not so long ago the main approach in medical research was basically "try stuff randomly on lab animals and see what has a beneficial effect". Now that we can peek into the internal workings of biological systems we can use a more direct, more engineering-like approach.