edit: there is also the fact that map compilers for gold source games have advanced far beyond what they could do back in 1999. The lightmaps and light sources alone can be far more intricate nowadays than what you would get from the official valve ones in 1999.
edit: there is also the fact that map compilers for gold source games have advanced far beyond what they could do back in 1999. The lightmaps and light sources alone can be far more intricate nowadays than what you would get from the official valve ones in 1999.