Unfortunately, the real world would say that an unmeasurable theory is just that. You are correct, it is a given. It is a given from a specific frame of reference. It certainly isn't universal or without flaw. Time dilation isn't necessarily something I would bet the farm on.Digress all you want, but you're digressing from reality.
The effect has been measured millions of times. Literally, given that GPS systems have to compensate for the fact that their satellites aren't as deep in the Earth's gravity well as what they are measuring.
It's actually a given, and I gave you the equation to calculate it, so... fantasize onward with your special world view.
The rest of us will stay here in the real world.
And seriously, I am exceptionally polite and patient, all I ask is that you refrain from the caustic speech. Passion and frustration are not compatible.