Mind you, physically based renderers also use a bunch of clever hacks upon hacks to be able to run in realtime. Nobody is simulating photons bouncing in the nanostructure of a material. We just have formulas thay say "for this roughness and metallicness, your material will look like that and it'll be good enough". We still abuse the hell out of UV maps to fake things, still include ambient occlusion (as a stylistic choice most of these days).

It's a different workflow that gives you consistency once you know what you're doing, as opposed to the days of Phong shading.