Complex sentence: But television news was a short-lived venture for him, and it was over radio that he presented and commented upon the news for four decades until his retirement in 1976, the longest radio career of anyone.
Split into simpler sentences: But television news was a short-lived venture for him, and he favored radio. Indeed, it was over radio that he presented and commented upon the news for four decades until his retirement in 1976, the longest radio career of anyone.