No, I don’t think so. I a theoretically perfect setup, putting the same signal into both channels will increase the level in the room by 6dB, so that’s why the pan law is there (to reduce the signal level when it’s central / increase it when it’s panned), and hopefully remove the change in volume that would happen. However, real rooms and setups don’t usually achieve this, which is why 3dB is there.
What I think would happen is that there would be more of a difference between panned tracks and non-panned tracks, but I don’t think the mixes would sound “bigger” or “wider”, just more extreme in terms of panning (like 60s recordings when some mixers had a switch instead of a pot for pan, although I don’t know the pan law for said mixers!). I’m making suppositions here, but I’d think there’s more to it than just the pan law to make something sound big/wide, but I’m prepared to be convinced otherwise.