Because some people believe that good gear should take a lot of time and effort to obtain, which is a valid belief. This is a matter of opinion after all. Not everyone plays to be the best, but to feel an achievement for getting where they are, a feeling that is (for the most part) lost with Abyssea.
There's different degrees of repetition. This is a whole new level.
That argument doesn't hold water, since the Abyssea zones have seperate memory entries as well as seperate DATs for the zones themselves. They're in every respect new zones. The only limitation is SE's resources to put more effort into it.
I would really like to see new census numbers. Everyone keeps saying Abyssea revived FFXI, which in my experience couldn't be more wrong. When Abyssea was initially released about as many people joined or returned to the game as have quit because of it. And when it was released it was considered a very new and fun experience, which is why many people praised it, and this includes almost everyone who blames it for destroying the game now. Lately all I see everywhere around me is people quitting, and all of them for more or less the same reason: "the game is no fun anymore". I wish I had actual numbers to back this up, but I don't, which is why I really hope some numbers regarding this are included in the next census.
I observed three stages to Abyssea:
1) After release some people were annoyed that all their achievements were basically annulled and quit the game. Others welcomed the new content and new challenge, while appreciating the eased level, but still to some degree rewarding old content.
2) People figured out Atma efficiency and Weakness staggers. AF3 and Atma kept raining in, while Empyrean Weapons became a realistic goal to many people. Old content was largely ignored, because more time was invested in new stuff, and with the next two level increases, it lost even more in its usefulness.
3) Empyrean Weapon grinding. Most people have what they need and just keep going on and on, for no reason other than having a better weapon, which makes little to no difference in the first place, since there's no content which requires it. This one may change with future updates (not really by a noticeable amount with this one). But at this point many people had enough, even some of the early Empyrean Weapon grinders.
By now I know a lot of people who quit. A few old players came back to check it out, some are quickly catching up to the point of being annoyed again, others have already quit as well. Again, this is just my personal observation, but I see it in such a large amount, I find the argument that Abyssea revived FFXI really hard to believe. I would really like to see official census data if this is a large-scale event or if it's only happening within my own environment.
Also, I know absolutely no one who bought a second account to play inside Abyssea, and, in fact, a majority of people with two accounts I know have quit.
Edit:
About inmates running the asylum, this place was made specifically for people to share their opinions with SE. While quite a large amount of suggestions are objectively stupid, I'm fairly certain the development team is smart enough to filter those out. Others are matters of opinion and should be regarded as such. And for that, this official forum is just the right place, because, as I mentioned before, it contains players from every part of the game, low end, high end, and everything within that spectrum.