I came across this today and found it quite relevant, both to the state of the games industry and my own university course (I study Gameplay Design and Production at Staffordshire University). A modder named Ghor produced a Garrysmod addon that acts as something of a partial source-port for the classic Doom games - I say partial because it is possible to use assets from both games in combination.
The results of this are interesting; Doom was released over twenty years ago now and Garrysmod recently turned six, but despite the difference in their ages the two games mesh like they were always supposed to be together. The more things change, the more they stay the same.
GmDoom video
Steam Workshop
The Old and The New
Moderators: GSH, VSMIT, Commando
The Old and The New
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