Still no excuse for such shennigans. Next thing you know, we'll be back to the 1850s where Congressmen were beating each other with canes.
The Congressman should be subject of a resolution of rebuke. Not arrest. Not impeachment. Not censure. Just a slap on the wrist to embarrass him.
You can yell all you want. You can mock the actions of the opposing party. But you cannot commit assault. And regardless of age differences, that 72 year old fulfilled the elements of common law assault.