Science does not and has NEVER worked like that. First...observations of facts that are not explained by current scientific knowledge. Second....formulation of a hypothesis that explains both the old and new facts. Third....verification that further discovered facts do or do not support the hypothesis. If yes.....hypothesis is "promoted" to theory. If no....formulate new hypothesis.
Science ALWAYS works from the very specific to the general and NEVER the reverse, although it continues to be tested by explanation of further new observed facts. And there are other ways to "test" theories outside of lab experiments.
Nobody has any problem with the theory of plate tectonics, but no laboratory experiment has ever been done (or can be done) to prove or disprove it. But it has survived the tests of explaining newly discovered geologic facts quite nicely.
Actually, Einstein's Theory of Relativity was a huge step in general principles, and was confirmed by many different specific, testable predictions, such as the bending of light due to gravity, to the slowing of the decay particles as they accelerate to the speed of light, and to the slowing of clock due to the gravity of the earth.