Overall, I think it wouldn't matter. If the services the caddie provides was banned, players would find other ways to get the info they need.

Also, the relative strengths of the players would not change IMO. Those that are top ten today, will be top ten without caddies as well.

If anything, play would probably only slow down even more. Compare to rally: the co-driver isn't strictly necessary, but allows the driver to drive a lot faster (and safer too).