To be fair, schmelling was very privileged to get footage of joe back then… not many got to study their opponents before a fight back then
In terms purely of skill? I'd say he's among the ten most skilled men of his size, ever. I'm not sure about p4p because who knows how all of that would work, is it realistic to expect a man of 115lbs to affect another human being the way Louis could affect any human being? I don't know about that. But in terms of guys weighing 200lbs or less, there's never been a more skilled fighter. As to how that translates into 250lb very skilled fighters, I'm unsure, that's very difficult, I suspect the size difference would be too much for him more often than not.
Louis was good, like really good. But to say he would beat the greatest of the strongest era of boxing is an absurd take. Liston,Fraizer,Foreman, and even Ali would all have him laying on the canvas having a sweet dream.
I think Louis is a stylistic foil for Liston, Foreman and Frazier. They’ve never met someone with Louis’ combination of intellect, power, handspeed and accuracy and I think it would be overwhelming. Beating up dudes like Lyle, Williams, Norton, Bonavena, Patterson and Quarry isn’t comparable to what Louis would bring to the table.
Louis is generally considered a top 5 HW. Most people don't have him as THE goat of HW but most people have him close. If we were to make a GOAT list averaging out everyones list Louis would have a very good chance of being number 1. The 70s IMO is the only era Louis wouldn't be the ruler of.
To be fair, if we take any heavyweight champ from the 70s they would DEMOLISH basically any other decade