How Did Tom Welling’s Clark Kent Lose His Powers in Smallville?

The Arrowverse’s Crisis On Infinite Earths revealed that Tom Welling’s Clark Kent from the Superman series Smallville no longer possessed the powers of Superman. Unfortunately, the cameo didn’t explain how Clark lost his powers or if the loss was permanent. There are a few scenarios in which Smallville’s Clark Kent could have lost his powers. The most likely explanations are probably kryptonite-related. The common green kryptonite is known to both weaken and strip Kryptonians of their powers. The latter consequence usually results in death as opposed to living a normal mortal life. Kryptonite, however, also comes in many variations with various effects.