I don't think it's untestable. All you need is a counterexample or two to prove it incorrect. Unless your proposition is that there are groups exploiting minor

I don't think it's untestable. All you need is a counterexample or two to prove it incorrect. Unless your proposition is that there are groups exploiting minority unsupported OSes but that they all remain successfully undiscovered, like Russell's teapot[0]. But as others point out, there actually is at least one known counterexample - WannaCry/EternalBlue. [0] https://en.wikipedia.org/wiki/Russell%27s_teapot https://en.wikipedia.org/wiki/Russell%27s_teapot