Time dilation is wagging the dog.

Tool: Clock (measuring time)

Subject: Cesium (changing its behavior)

Compare this to:

Tool: Tape measure (measuring distance)

Subject: Person (shrinking when older)

We would never say that the tape measure dilated, or say that the tape measure stretches when it measures older people.

Why are we saying that time dilates?

Because Einstein said it.

What Einstein did not know was that we are moving through space at our fastest rate together with the entire Milky Way. We've been doing that for 13.8 billion years, ever since the materialization process took place. Nothing much stopped us from going at that fastest speed.

But Einstein did not know. Only later did the Big Bang become available. For sure, Einstein would have looked at that new information. But he did something remarkable. Or better, he forgot to do something, which is remarkable. He did not double check to see if there was a mechanical reason for his GR.

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Newton had his feet on the ground, but on a planet floating through space.

Einstein simply put all our feet on space, and though we should then still focus on matter, some of us wandered off and focused on time being something it cannot be.

A tool that dilates is a horrible tool.

Can we still use time dilation?

Yes, but only when considered the important aspect of the framework that Einstein introduced. So, time dilation says nothing about time, but it indicates in how far matter changed.

The Cesium in the clock, ticking sturdily on planet Earth, changes behavior when placed in a spatially distinct location.