He could pull the trigger when he was younger. He went with sweeping shots and drilling one-two's when he was older when his target was in position, and picked his shots well. But remember the combinations he hit in his youth? The improvised half-uppercuts, sometimes leveraged, sometimes only arm-punches? He saw his opponent off-balance and immediately launched. The old George lacked that in a big way.
The trouble with old Foreman is that every hard punch he lands on his younger iteration will drastically affect him in the present, to the point that he may end up horribly punch drunk by the close of the fight. Lose lose situation for him, really.