Does this recent DISCOVERY really give us the cause of Gravity?

A correct theory of gravity will show us these four (4) things:

1. It will show us why gravity also acts like acceleration (principle
of equvalence).
2. It will show us the actual cause of gravity.
3. It will show us why gravitational mass and inertial mass are
identical.
4. It will show us the speed of gravitational attraction.

Newton said gravity was acting at a much faster speed than Einstein.
Which one of them was right?

http://www.amperefitz.com/why.we.have.gravity.htm

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