The speed of light is the same in all references. Whereas, inertial or finite reference is relative. This means the speed of light is the universal reference by which we should be explaining the universe.
The speed of light is also the ground state or zero state of the universe. This can be inferred from special relativity. Mass cannot go the speed of light or it would take infinite energy. Therefore a mass based universe has to exist at a reference less than C. If we look at the net conversion of mass to energy and energy to mass, our universe goes net mass to energy; back to C toward lower energy.
This simple logic, implies the universe began at C reference, where time and space are irrelevant, with mass/energy condensing, which meant the local reference needed to slow to less than C. Now we have the BB singularity with plenty of mass. To go from C, to less than C, we need to put on the brakes, with the relativistic mass/energy difference the brake heat that will expand the singularity; boom!
Since the universe has finite mass, this did not tap out the resources of the C reference, but was only a blip. With C still the continuous and universal phase and reference, the movement of the BB universe was now back to C. All the forces of nature give off energy when they lower potential; matter back to C. Gravity causes space-time to contract in the direction of C reference.