If the idea is to reduce the rules and simplify, wouldnt taking this rule out make golf easier to understand. Also, I will go opposite your question. If one can leave the pin in, Wouldnt the advantage be equal for everyone?
Finally, lets say the pin is tucked left side back and I hit right side short and so does my playing partner. It would save time and energy rather than walking to the pin to get it out and walking back to make my stroke.
From what I understand, the R&A and USGA want to simplify the rules of golf. Rumors I hear is that maybe they want to have a max of 20 rules. Golf is on a downward spiral and making the rules easier to understand is part of the objective of trying to get back the growth of the game.
But you just never know with the R&A and USGA.
People are afraid of change. Who cares if the pin is left in or pulled out. On any shot outside the green the player has the option, but on the sacred green, he cannot.