Yes, it is an illusion.
First to emerge if we look at the origin of universe, was space - if you are an observer and you watch empty space time simply do not exist.
When matter is created - its then when time comes into being.
We have seen strong evidences the most basic and fundamental forces in nature before anything actually came into their current form are : magnetism + energy + spin.
These are way more complex than we know, magnetism is always in loops and energy expresses itself in loops aka on magnetism. In our observation we have found energy and magnetism are intertwined.
Both magnetism and energy are bundle of ingredients that are coupled as one. When energy expresses in loops and magnetism locks it at the quantum level then we see pro-particles emerging and collapsing in QF. (some even in Q Mechanics call it strong or weak nuclear force)
When we smash these particles in LHC they simply vanish in thin air within seconds leaving a decay which further gives us the evidence that nothing is vacuum but we ourself are on ZPE F and its all around us where the actual merger or handshake happens to create matter as we know. So the process is simple which is a cascade. One more thing on which we have to wrap our mind energy is always a decay that we see, we can only see it’s after affect and energy never can return to its original form its fades, dis-integrates or disperse till basic fundamental forces do not process it again to create what we call as matter. (this is why when we see merger or dis-integration we see energy release - eg fusion or fission)
Magnetism + Energy + Spin = mass + density = curvature = gravity (quantum gravity)
(in large scale when we see gases, dust and energy spike - when spin happens we have seen galaxies coming into being)
(and then GR comes to explain gravity and curvature - prior it GR don’t even exist)
Mass + density = formation of matter = heat = light.
Matter formation = emergence of time.
So all these 3 - gravity → light → time are emergent in local dimension.
When the fundamental forces take over a local zone i.e Magnetism + Energy + Spin - all these three emergent - gravity → light → time breaks and so does our physic, black hole are a fine example which are the fundamental forces in real action and even what we see or describe is not the black hole itself but its accretion disc, till accretion disc is not formed we have no gravity → light → time - all these 3 emerge when we see the formation of accretion disc aka matter formation.
Space does not work on time because time does not exist in space, for space to understand its events that define space, we are just a blip in space event scale, there are million, billion and trillion who came before us and who will come after us.
So its true space-time as per GR and also other wise is just an illusion because its an observer affect for eg, a jet takes off from the run way, for the observer its leaving, a person moving in the car for him jet will be stuck on air, for a person sitting the jet will zoom out, for the observer at the run track the jet will show as arriving, for someone observing in radar he will see entry and exit point of the jet but for the pilot nothing as such happened. So spacetime is actually the observer affect.
In realty space does not interact with local emergent ie. gravity, light and time. So space never bends its the content in space that bends as we know there is no vacuum anywhere but we are seeing the affect but cannot scale the vacuum so it feels as if space is bending (defined as curvature).