Einstein created Spacetime to explain the behavior of matter. He did not declare Spacetime a something that is an actual aspect of the universe.

A measure tape is real, but it is real in two very disconnected manners.

1/ The material that makes the measure tape is real matter. Yet the matter does not do the measuring.

2/ The tags on the measure tape are real tags, but they were placed there by people. These tags measure distance, but they do so in a human-based construct.

Let's make this obvious further.

If the measure tape measures all people on a daily basis, combined in one large computer, then a surprise awaits us.

For some folks, the measure tape stretched. Where at first they were a certain height expressed with the measure tape, at some point the measure tape stretches further because less measure tape is now used to get to the same height.

Okay, here is the explanation. When folks get to be older, they can shrink. The measure tape did not stretch, the people shrank. I was wagging the dog with you, so you can recognize how you are wagging the dog with Spacetime.

When other physicists started wagging Einstein's Spacetime, Einstein objected.

Result: These other physicists ignored Einstein.

I hope you don't ignore Einstein, André.

Spacetime the Einstein Way is all about the behavior of matter and not about space or time.

Spacetime the non-Einstein Way is using a warped Spacetime reality to show what happens to matter.