Being _hyper_ reductionist, the standard model of physics, which describes, to an extremely high degree, the interaction (creation, elimination, and chance of one thing turning into another) of particles that constitute "stuff" (matter / energy) does not account for the interaction of matter via gravitation.
Most things interact with each other, they create "particles" to exchange force / energy (actually in the case here much of this is actually virtual particle interaction / creation). An example of this is when two magnets are interacting with each other, the repulsion/attraction that the magnets / and magnetic fields, the force carriers there actually described by best by "virtual photons" https://en.wikipedia.org/wiki/Virtual_photon#:~:text=Virtual....
The whole standard model is like this (protons/neutrons exchange gluons via the strong nuclear force).
For gravity, there isn't a good "particle" we've found that can accurately describe how gravity behave. It's good to note here a "particle" is what is used to "quantize" something, and so quantum mechanics is the study of how these subatomic particles interact and are created when things like protons are smashed together in a particle accelerator.
Gravity, on the other hand, behaves more like a classical theory (in the sense that it is a field, rather than a discrete quantized energy exchange). In the parlance of the field, mass, appears to cause a curvature in space time according to the rules (quite accurately predicted) in general relativity.
This appears to be some sort of more reconciliation by acknowledgment of the different aspects of the behaviors of the models (GR vs QM), and chooses a path to verify this by looking at the breakdown of matter (in this case, entangled quantum particles) in a asomtomic limit that might be imposed on a quantized theory when that is subatomically reconciled against a continuous field like gravity.
(My own notes)
This might be indicating that there is a continuous nature (or at least continuous at the scales that these subatomic particles experience) such that when the particles interact with the continuous field, their movement creates some snapback of the field (thinking how movement in water creates microscopic cavitation) which disrupts what would be a continuous laminar flow in the water case, creating macroscopic turbulence (in this case disturbing the entangled particles)
* Edit: a little clarity / notes on the SM/QM/GR overlap