Gwynn obviously faced better talent, and you definitely got the "white" part correct, but they weren't slobs. Baseball was THE sport in America at that time, thus EVERYONE with any athletic ability played it. Granted, your talent pool was like 1/10th what it is now due to smaller population and the obvious demographic barriers, but the guys who made it to the majors back then were still the most elite (white) athletes and ballplayers of their time. It's not like some rube from Nebraska could just show up at Yankee stadium with a bag on a stick over his shoulder and knock on the door and be like "hey! I'm good, let me play!" Though the modern farm system wasn't developed until the 40's, they still had very extensive minor leagues back then and just like today you had to work your way up. You also have to take into account how much of baseball is skill-based as opposed to being purely athletic-based. "Baseball skill" translates throughout the eras to a large degree. Ken Griffey played against and struggled against a guy like Rick Reuschel. 20 years earlier Rick Reuschel was getting clobbered by guys like Pete Rose. 20 years before that Rose was getting dominated by guys like Warren Spahn. 20 years before that Spahn was getting smacked around the yard by Jimmie Foxx. 20 years before that Foxx was getting punked by Walter Johnson and so on... There's no argument that the talent pool is much larger and players today are obviously bigger, stronger, and faster. Duh, of course they are. So ya, you time machine 1930 Lou Gehrig into the 2017 Cubs lineup and he for damn sure isn't going to be hitting .340 like he was 75 years earlier. However, due to how much natural skill is involved with baseball, I think your guys like Williams, Ruth, Cobb, or Gehrig would still be elite today if they had been raised with the same nutrition and physical training opportunities as modern players.