If we're in a simulation / video game, then there will be times "reality" needs to render a bunch of NPCs to add realism. The PC can maintain a high presence frame rate even under heavy crowd loads. It probably has as much headroom as a Game Boy emulator on a modern smartphone. You'll NEVER lose frames, however AI behaviour will always remain the same unless patched.

Our MMO VR experience might be about to experience an update. Like that Canadian CGI cartoon ReBoot.