Could Holmes have beaten a prime Ali? Could Lewis have beaten a prime Tyson?, Could Tyson have beaten a prime Holmes?, Could Marciano have beaten a prime Louis? Could Johnson have beaten a prime Jeffries? Could Tunney have beaten a prime Dempsey I think the answer is always could have yes but it would have been a lot harder to do vs the younger,primer,fresher version and I doubt if they would have
Could have? yes, would have not sure, this coming from a Jack Dempsey freak! Styles as we all know make fights and maybe Gene had the wrong style for Jack, we will never know.
The prime Dempsey had some trouble with clever, scientific boxers. I think it would be possible for a prime Dempsey to beat a prime Tunney but it's not a sure thing.