I might have to disagree with the other comments here actually, with a stipulation. You can’t (currently) make your time differ from the real people around you, so you can’t spend a day in vr and come out with a year passed in your mind and memories, but there’s no reason you can’t have time change for the npc’s in the simulation. For example you could be in a vr spaceship on a video call with someone while you’re going near a black hole, as you get closer, assuming an analog walkie talkie type transmission, their speech would be faster and tone shifted higher and everything since your time is “slowing down” next to the black hole, making everything go faster outside the black hole’s main influence, or have a ship going relativistic speeds have their transmission slow down with their video call due to the time dilation effects. This could be an accurate simulation because time always passes at one second per second for a given observer from their own perspective, so it could be indistinguishable from the real effect as long as it’s pre-programmed and limitedly interactive and everything. That might be the lame answer but I still think it’d be pretty cool to see something like simulating scientific concepts that in a game that could be made today. Unfortunately your time won’t pass any differently from the actual people around you though. There’s a game somewhere made by like MIT that simulates what it’s like if the speed of light is near walking pace, that’s probably about the type of thing you could get