The remastered edition of Quake, launched just yesterday by Bethesda on PC, Xbox One, Xbox Series X and S, PS4, PS5 and Nintendo Switch, would violate his GPL license, as noted by many members of the gaming community for decades.
In 1999 John Carmack, then head of id Software, released the source code of the Quake and Quake II engine as GPL (General Public License), allowing them to be studied and used by the community. The GPL license requires that any software derived from the source software must be released under the same license.
The source code of the remastered edition of Quake, which evidently derives from the original Quake, has not been released to the public, however, creating a precedent. Some experience it as a real betrayal of the community that has been behind the game for more than twenty years, enriching and refining it.
Some hope that Bethesda will fix the situation soon by releasing the source code. The worst case scenario is that the Free Software Foundation takes Bethesda to court.
In reality there are also those who affirm that there would be no violation in place, given that the GPL license covers a single version of a software and that with the subsequent ones the contract can be modified, thus excluding any possibility of recourse. We’ll see how the situation evolves and if Bethesda will say anything about it.