Apples and Oranges.
Yes, Yoshi-P is a fan of PvP. I also bet that he's a fan of a lot of other stuff too. He's also the director of the game and knows better than just make FFXIV to his own tastes. A glaring example of this is crafting and gathering that he has no interest in yet is still in the game.
You saying that you wouldn't ask for glamours to not be in the game is completely meaningless to this argument, because it's entirely possible that glamours simply don't bother you as much as dueling would bother others.
A lot of arguments can be used for a lot of different things in this game. That doesn't mean that they aren't valid arguments or shouldn't be considered. Just as people are voicing that they want open-world duels, others can voice that they want PvP to continue hidden in instances.