These two cases aren’t the same though. Doom built a whole new genre by building on Wolf 3D’s foundation, it just didn’t have a name at the time. Very few 90s fps games actually play like Doom, or even try to. They all got their own thing going.
GTA clones definitely wanted to be like GTA, I can tell by just looking at them. I didn’t play any GTA inspired games besides Retro City Rampage so I don’t know which titles in particular deserve to be seen as knockoffs but they were out there.
These two cases aren’t the same though. Doom built a whole new genre by building on Wolf 3D’s foundation, it just didn’t have a name at the time. Very few 90s fps games actually play like Doom, or even try to. They all got their own thing going.
GTA clones definitely wanted to be like GTA, I can tell by just looking at them. I didn’t play any GTA inspired games besides Retro City Rampage so I don’t know which titles in particular deserve to be seen as knockoffs but they were out there.