"better and better models of the world" does not always mean "more accurate" and never has.
We already know how to model the vast majority of things, just not at a speed and cost which makes it worthwhile. There are dimensions of value - one is accuracy, another speed, another cost, and in different domains additional dimensions. There are all kinds of models used in different disciplines which are empirical and not completely understood. Reducing things to the lowest level of physics and building up models from there has never been the only approach. Biology, geology, weather, materials all have models which have hacks in them, known simplifications, statistical approximations, so the result can be calculated. It's just about choosing the best hacks to get the best trade off of time/money/accuracy.
We already know how to model the vast majority of things, just not at a speed and cost which makes it worthwhile. There are dimensions of value - one is accuracy, another speed, another cost, and in different domains additional dimensions. There are all kinds of models used in different disciplines which are empirical and not completely understood. Reducing things to the lowest level of physics and building up models from there has never been the only approach. Biology, geology, weather, materials all have models which have hacks in them, known simplifications, statistical approximations, so the result can be calculated. It's just about choosing the best hacks to get the best trade off of time/money/accuracy.