Gravity is a theory
There is the scientific theory of gravity and the law of gravity.
The law is the mathematical relationship that describes what happens from observations, it is an analytic statement of observed fact.
The scientific theory is the researched and tested framework for the how and why of the observation, in this case Einstein's theory of relativity is used to explain the how and why of Newton's law of universal gravitation.
Further, to become a scientific theory, an idea must be thoroughly tested, and must be an accurate and predictive description of the natural world.
Relativity is a theory, a shitty one that's wrong; the Sagnac Effect experimentally proves the existence of an aether.
But the gravity observations are still there, even if the theory is wrong.
