ok, so you did them when cop launched, and as the content for it was released(kinda like how i did)
while i didnt 1/1 several of them, i didnt fail alot either(some people may even say i cheated cuz i did it with a 5 blm/rdm team all the way through, was one of the first to use that style of team for this and it worked GREAT, especialy pre nerf)
cop was an awesome experience, but i also dont think it was due to the level capping of the areas, it was due to the mechanics of the fights.
if it was scaled to level 75, people woulda had just as much trouble on it as they did when the stuff was 40 capped, or 50 capped. but it was story driven with progression. so capping it and raising it slowly made ALOT of sense. especialy since back then most people didnt have 75s yet so they were still having to level up to reach the next cap available.
The discussion which this which relates to whats at hand. These dungeons are not cop. They arent story or pgoression driven. They are just straight content. You dont need to put a cap on content and lower peoples levels. The entire reason they are releasing 2 dungeons, and not just 1, is so that there are 2 ranges for people to do them at. 1 for lower people and 1 for people who are capped(or near capped).
The lower dungeon isnt meant for people to gear up their 50s(obviously) or present them a major challenge, that is why they added the 50 dungeon.
So main arguement going around from there is that people feel the 50s shouldnt be allowed to get the 30 dungeon done because the content isnt meant for them as much, and therefore they should be restricted in how they do it.(fewer people fall into this catagory then the next)
The rest of those wanting restrictions, are those who are capped, who are mad that they didnt get 2 rank 50 dungeons, therefore they want to find a way to make SE turn the 30 dungeon into a challenging dungeon for 50s using a level cap, and dont care if others want it or not, as long as they get what they want(another instance to do at endgame basicaly)