I thought general relativity actually proved that time was a fundamental dimension of our universe [1]. I'm really unsure because I have never studied general relativity, but I thought it used Reimanian geometry [2] to solve a bunch of things using 4D manifolds [3]. Is the reason you say that a consequence of relativity theory is that time isn't exactly a property of the universe because the 4 variables of spacetime are all distances [(c*t, x, y, z)] as opposed to having 3 variables being distances and one time [(t, x, y, z)]? Or is it simply because Relativity proves that time isn't universal etc ?

> That is, "time" doesn't exist, but we created it.
Honnestly, I very much like the Wikipedia introductory paragraph on time:
"Time is a measure in which events can be ordered from the past through the present into the future, and also the measure of durations of events and the intervals between them" [4]
I think time is just a measure used when describing dynamic systems (where past, present, and future make sense). Assume for a moment that the Big Bang happened at t = t_BB, and assume that for all t < t_BB, there was absolutely nothing in the universe and nothing was happening. Would time make sense in such a pre-Big Bang universe ? I think time is a fundamental property of a dynamic system because without it, the said system would not be dynamic. I'm not sure however that time is a fundamental property of the universe. Maybe of a dynamic universe ? In which case time would be a fundamental property of our current universe, in accordance with Einstein's theory or relativity, but not in a pre-Big Bang universe such as the one mentioned just a few lines ago.

Finally, from the article:
> McTaggart argues that time is unreal because our descriptions of time are either contradictory, circular, or insufficient
I think Einstein would probably agree with him in that time is at least contradictory [5]. Although I'm not sure they would mean that in the same way. To take McTaggart's A-series argument:
> Specifically, [McTaggart] argues that since every event that occurs will at one time be the future, at another time be the present, and at a third time (and forever henceforth) be past, every event exemplifies or instantiates every temporal property: futurity, presentness, and pastness. Since these properties are mutually exclusive (they cannot be co-instantiated), the A-series conception of time generates an absurdity, a contradiction. If both parts of his argument are sound, then time must just be an illusion; it has no genuine ontological status.
I disagree with this logic. Notions of past, present, and future are mutually exclusive at any given time t; but events can of course go from future to present to past. It just can't be more than one at the same time. Kinda like when you're sprinting a 100m race, you can't be before, on top, and after the finish line at the same instant. But you can go from one to the other without questioning the notion of distance. The analogy is far from perfect, but that's how I see it. I may have misunderstood his argument though.

[1] https://en.wikipedia.org/wiki/Spacetime
[2] https://en.wikipedia.org/wiki/Riemannian_geometry
[3] https://en.wikipedia.org/wiki/4-manifold
[4] https://en.wikipedia.org/wiki/Time
[5] https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experim...