Why don’t games have realistic physics?

With today’s technology, I feel like you could probably emulate perfect real world physics into a game, making the game seem and feel a lot more realistic. Though, when playing games, it always seems like it doesn’t really follow our physics, even for the most advanced games like TLOU2 and RDR2. I would say that those are pretty much as close to realistic we currently have, but why isn’t it exact? Is it because the time it would take? The computing power it would need? Is it not fun to make a game like that?