There is no way Rogers Hornsby of 1922 is the same guy if he played in the modern era. He would have better conditioning, a better diet, a raft of personal trainers, his own coaches and a zillion people in the background doing everything from carrying his bags to turn-down service. The machine surrounding Pujols since he entered the majors simply dwarfs what Hornsby had, plain and simple.
The 1920s, as fantastic of a time as it was, pales in comparison to the modern era. The "perks" Hornsby and the players he played with wouldn't amount to what today's AA players get today, and that was for the stars, not the regular players. The food was different, the travel was different, the whole culture of "fitness" was far, far different.
You put a man with the raw natural ability like Rogers Hornsby in today's game, let him come up through the system like Albert Pujols did, and you'll have a hitter that will terrorize modern pitching like Barry Bonds in his prime.
When making the comparison between Hornsby and Pujols, you have to first level the playing field. If you're just going to take each player within their own era, modern players will always look better, simply because we've had 80+ years to improve on the system. Take them equally, and they look very much alike.
Keep wreves in General Talk in 2011!