So, ironically, the past - which does not have an actual current ontic existence - is all that matters to us.
Exactly. We might like to imagine that we're living in the real world but in point of fact we're actually living in the wake of it. Because the speed of light is so mind-numbingly fast this has a negligible effect on the way we comprehend reality because of the "distance" scales at which we live our everyday lives. However, negligible is not synonymous with irrelevant when it comes to applied metaphysics and when it comes to the ontological status of our observations we cannot ignore the fact that the "distance" scales which we observe are nothing more than holographic representations of a reality which no longer exists. When the science of physics finally grasps this blindly obvious truth then the path to the unification of its models will be self-evident.
"Behind it all is surely an idea so simple, so beautiful, that when we grasp it - in a decade, a century, or a millennium - we will all say to each other, how could it have been otherwise? How could we have been so stupid for so long?" - John Archibald Wheeler, PhD
Reality comes to us only in the faulty moments we manage to briefly grasp as myriad changes pass us by. Our consciousness is akin to being in a car and pointing out landmarks while being unable to discern all the fractal detail between and in those landmarks.
Yes. Ontically the universe must be a fractal continuum because only such a model can account for the self-organising complexity which we observe, even though the way we choose to model such complexity is entirely arbitrary.