(I missed your comment earlier, sorry!) His real name may be "Matthew Earl", it seems https://mastodon.cloud/@mattsramblings . I stuck his three Quake-rendering videos together in a playlist: https://www.youtube.com/playlist?list=PLVJ2vTa3CVnRRsJvvcdR3... . He also has a video on Quake 1 and 2's lighting https://www.youtube.com/watch?v=bxientPsqRg among his videos https://www.youtube.com/@MattsRamblings .