I really hope you just that "can" is a typo for "can't".
Otherwise, you fail to see the first rule of Gamers, "If an advantage exists, they will use it.", much like players did bypassing Garuda's Astral Flow. I think it's very evident that gearswapping during battle was never intended to be advantageous in FFXI either, but we saw how that turned out and it's pretty much required for every and anything nowadays. Best choice is to completely block off gear swapping during battle and leave the rest of us players to fend for ourselves.