You're leaving a few things out, JAB. If you're going to study Boxrec, you need to study it a bit more closely. Conn started boxing professionally when he was 16. (And for the record, he NEVER fought at lightweight.). He debuted at sixteen, weighing 136 and grew steadily till he weighed 148 at eighteen, 156 at nineteen, 162 at twenty and 167 at twenty-one. For the rest of his twenties, he ranged from 167-188. (Currently GGG is thirty-two; when he was eighteen in the amateurs, he boxed at 140, around the same or a bit lighter than Conn at the same age). The 8-6 record you mentioned was earned ENTIRELY as a minor. He was 16 or 17 for all of those bouts. Five of those six losses involved a 17 yr old losing to a 20 yr old and four of the losses were avenged when Billy was finally old enough to drink ! In addition, boxers fought more frequently then. As a 16/17 year old, Conn fought 15 times in 13 months, sometimes twice in the same week, and sometimes on consecutive days ! So yes, you're right, a sixteen year-old Conn would probably not be a great sparring partner for a 32 year old GGG. But reverse the ages, and have the sixteen year old GGG (or any version of GGG) spar with the twenty-three year old, 174 lb Conn who was outboxing the twenty-seven year old 200 lb prime Joe Louis, and the mismatch would be even worse. And for the record, I'm a big GGG fan. But some of these posts are frankly, embarrassing.
Joe Luis was considered by many as the greatest HW of all time. Beating up fighters who were smaller and bigger than himself. To my eyes Luis looked much bigger than GGG so it would not be a practical match. Maybe GGG vs Bob Fitzsimmons? -))
Lol, youve been trolled!! I wouldnt pick any fighter over the best version of Louis with the possible exception of a peak Ali, and I wouldnt pick a middleweight over any version. Check your inbox.