I guess I see that more as single-player vs multiplayer rather than PvE vs PvP. But I think your point is that the emphasis shifted from an entirely developer-c

I guess I see that more as single-player vs multiplayer rather than PvE vs PvP. But I think your point is that the emphasis shifted from an entirely developer-created experience to one where other players are a major/dominant part of the experience. This shift didn't take that long, though, with multiplayer-only games becoming prevalent (Tribes, Unreal Tournament, Quake III Arena, etc.) even before the 1990s were out, and single-player mode becoming a vestigial element even in those games that still included it before the end of the next decade.