Space as a privation? Preposterous, even just from a logical standpoint. Time as a concept? Depends on your definition of concept. Space can be described as a concept too. Both may be the single a priori known properties of the universe (i. e. they are fundamental to our perception of it themselves and therefore most likely not something generated only by our perception itself). Space definitely is not just emptiness, if you would take it away so to speak our universe and our perception wouldn’t exist.
Spacetime is simply another concept, I have no idea how you get the idea that we couldn’t combine the two. Reduce the spatial dimensions into one single axis, then use time as the other axis, and you can easily follow the paths of events along their worldline. This worldline changes if spacetime is warped, for example by being redirected towards a planets central mass. Voila, gravity. (I know it’s a VERY simplified explanation, but that’s basically what it boils down to from my understanding). It’s not even that difficult to grasp. Is it a model? Of course! Is that model actually reality? Probably not. Does that matter? For most people no, for theoretical physicists a lot, but this model explains nearly all observations we made so far AND predicted phenomena like black holes way before they were observed directly. A strong indicator that it’s at least a good approximation of how the macroscopical world works. The fact that this breaks down inside a black hole shows us that the theory is incomplete, but that was to be expected.
Also, mass is an observable trait of specific forms of energy, so there. It is theorized to be caused by matter sort of attracting and interacting with Higgs boson particles (which we were able to observe already). It in turn causes matter to warp spacetime. Again, a strong simplification, but you OP seem to be unable to grasp even simple a priori concepts like space, so probably best to keep it at that level.
And of course, the evil jews want the universe to be thought of as relativistic because…
I really have no idea what the point would be. Is this about the stupid conflation of the two meanings of relativity again?
Last but not least, that Einstein got huge opposition to his theory at first is normal procedure in science, contrary to what you believe scientists don’t just accept anything without questioning it at first, and the theory of relativity went against the classical believe of an absolute universe, so of course the opposition was strong at first. It wasn’t silenced by evil jews but by the model proving that it explained the universe better than what came before.