The earliest doom variants once the source code released started adding features that weren't faithful to the original dos version 1.9.

Even Boom which was a pretty conservative codebase that focused on limit removal for level editing added weird things like weapon recoil pushing the player back when you shoot a weapon.

So chocolate doom's name is wordplay on "vanilla doom" - it's the version of doom we all played in the 90s just updated with current i/o libraries (libSDL) so it can run on modern platforms.