Ethan, This is an excellent article.
Except. You forgot to mention that you were echoing René Descartes from the early 1600s. Predating Newton by about 50 years.
Descartes made precisely the same scientific, truth by replicable observation and measurement, argument for the reality of time and space outside our minds. If I can prove to you that you can see this too, then it must be real. This is because there can be no other definition of reality beyond what our minds can see and agree is true ("I think therefore I am.") But the real reality is our natural language that makes all this kind communication among Homo sapiens possible. Despite what you may want to argue, it is natural language that is fundamental to any reality that we can agree exists.
Here is the detail on Descartes (including what to read of his writings, some of which are pure popular garbage, but some not). There are reasons why Descartes is considered the father of the Age of Reason, the Enligtenment, as well as the father of Cognitive Science, and one of the great physicist/matheticians of his day.
Second, what is "fundamental" is, I am guessing, just what is. IT JUST IS. Here is how Feynman taught that. I realize I make the case differently through Feynman's armchair lectures, but I believe this slant on making your case is also quite interesting scientifically from a brain computation perspective:
https://medium.com/liecatcher/physicists-are-the-best-liars-c8e9ccfcf6b4
Most important of everything that I think Descartes argued was that our brains work in a way that the questions (and NEW BEAUTIFULLY CORRECT answers) will never stop. You can dig and find answers, scientifically, but you will always be able to dig more, and find more answers. You will never find "God's Perfection" because of how the human brain works. That is, by Descartes, the proof itself, of God as Nature (i.e., reality).
From my perspective, this is beause the neocortical brain is at least a hundred million classification/discrimination computation engines which can alway find AND COMMUNICATE TO OTHERS OF OUR SPECIES new classification/discriminations to discover about anything we can observe and measure.
https://medium.com/liecatcher/uniquely-human-7b14099b7462
In essence, Ethan, physics need to study what is in plain sight observable. People seem to miss what they all see most clearly. Language is a window on neocortical computation, and that is a window on the only reality we can know as truth. If you want to explain something, explain the computations and the computational origins of the linguistic universals of grammar. Explain the universals of syntax and semantics and human memory and communication that any normal human baby can learn, and why.
From that you will see that always, as Descartes before you clearly saw, nothing will stay fundamental very long, as long as science exists, except that God does play dice twice (and probably three times). This is because our brain computations just play dice, too. That is more fundamental than reality itself, which is real. A la, Descartes.
https://medium.com/liecatcher/god-doesnt-play-dice-once-but-twice-d59045fcec13
Again, thanks for a really good article. But if you want to know what is real about time, study the linguistic universals of tense. Your brain knows time well and is 'in the limit' already. You and I, and everybody else as well, are discriminating/classifying about time in every sentential episode of communication with other humans. We "understand" each other. That is the true fundamental that both exposes, and hides, ultimate truth. And has no end if Descartes was right, based on his "in plain sight" arguments, which you can read.
