Tough one. Prob depends on the kid. At 4 they won’t understand much of the game but would probably really enjoy the environment and excitement.
We took our son to his first Husker football game at 4yo, the 97 Orange Bowl. He had an absolute blast….then feel asleep through the 2nd half of the game. We sort of tailgated a bit in the parking lot and he never missed a chance to yell GBR at any Tennessee fan walking by. Probably would’ve made it through the whole game but it was a big long day for him. Glad we took him.