Job uses this question to mock the weakness of those men. Alternate translation: "The strength of their fathers' hands could not have helped me ... perished." (See: [[rc://en/ta/man/translate/figs-rquestion]])
Their strength perishing is a metaphor that represents no longer being strong but weak. The phrase "mature age" refers to them being old. Alternate translation: "men who had become old and had no strength" or "men who had become old and weak" (See: [[rc://en/ta/man/translate/figs-metaphor]])