I know what you’re saying abouth the advantages Rose may have had playing in modern era stadiums. However, Cobb never had to worry about outfielders like Willie Mays stealing base hits nor did he face pitchers like Bob Gibson. Cobb played during a time blacks were not allowed on the same ball diamond as whites, whereas Rose played against the best the game had to offer.
It goes beyond that. Cobb played in an era when all team travel was by train, all games were played during the daytime, fielding gloves were like mittens compared to the gloves of the 1960s, some stadia did not even have outfield fences, just a rope to distinguish the furthest boundaries of the outfield. Training was much different between Cobb's time and Rose's time. It blurs to the point that you can't distinguish who had an easier path to 4000 hits.
Tris Speaker and Walter Johnson are requesting recognition.