A couple notes to add:

Brook trout do tend to over-populate and stunt...unless there is little fishing pressure and the lake gets a population of large fish to eat the smaller ones. Same as a bass pond or low-land reservoir.

Cuts and goldens tend not to over-populate and stunt but if everyone keeps the big fish, the only remaining fish will be small.

The nutrient levels in the water are the single most important factor in how big the fish will grow. Even golden trout have trouble growing big on just midges. Since the nutrient level depends on the rocks and soils, different areas will have lakes of different nutrient concentrations. For example, in Idaho the White Clouds tend to have bigger fish than the Sawtooth Mountains even though they are close to one another. Reason being is that the White Clouds have more sedimentary rock.

Keep those dreams of big, fat, stupid trout just waiting for you after a hard hike. The truth is the harder the hike, the less fishing pressure and the better the chance of big fish. Just combine that with reseach of what areas are known for bigger fish.