There are quite a few ideas! Myself, I would bet on Polymarket that there is something more fundamental than curved 1+3 spacetime. Some are, as you said, in th

There are quite a few ideas! Myself, I would bet on Polymarket that there is something more fundamental than curved 1+3 spacetime. Some are, as you said, in thermodynamics. In the String Theory, 1+3 is a somewhat reduced space from original 26 dimensions or so. (This "somewhat" is the core issue.) So sure, "The idea that spacetime is emergent and not fundamental dates back to the 60s" would work as an awesome opening of the paper.