Weak Experimental Test of General Relativity

Space.com reports in 2022 that the Theory of General Relativity GR just passed its most rigorous test yet. What was tested was the postulate of GR of the Weak Equivalence Principle WEP stating that all bodies show the same gravitational free fall, which was tested by Galileo dropping objects from the Tower of Pisa 1589-92 as a test of a prediction of Newtonian Mechanics NM. 

WEP is thus a postulate of GR, while WEP is a consequence of NM. While it is meaningful to test the validity of a postulate, it is not meaningful to use a successful such test to confirm a theory based on the postulate. If we take 1+1=2 as postulate of our favourite pet theory, we cannot say that we have confirmed our theory by verifying that 1+1=2 (as postulate). 

Since WEP is a consequence/prediction of NM, it is meaningful to test it like Galilo did to give evidence that NM is correct. 

But a successful test of WEP does not confirm GR, since WEP is a postulate of GR and not prediction. 

Modern physics is strange.