Physics based rendering. Basically good texture shaders that work like materials work in the real world. Since that has been developed artists working with computer graphics in movies and games more or less don't have to worry about making something look realistic.

Every texture has values for color, reflectivity, subsurface scattering, fresnel, roughness and probably a ton more values I forgot. That gives you everything real light does when hitting a surface.

I think Wreck it Ralph was one of the first movies to use the techniques. I remember reading something to that effect alongside tutorials on how to get PBR into Blender. I think it took very little time for PBR to get into basically every graphics software. And nowadays when you buy textures they all come with different textures to set the correct values for PBR.