No matter how skillful or challenging you make it the battling is still going to become repetitive and boring. Once you get the hang of it I mean. A lot of people on this forum sight dark souls as being challenging. Once you get the hang of the gameplay though its all a lot of boring soul farming for upgrades.
Now multiply that by X number of years playing an MMO? I don't see what you're expecting them to do exactly.
I could hardly disagree more. If the challenge continues to escalate, it will never become entirely repetitive. As a couple of examples with PvE style content, look at Rock Band/Guitar Hero. Sure, there are different songs, but you're essentially hitting the same 5 buttons over and over. Look at the Smash Bros. Series. Each character only has ~20 moves, but even against high level computer opponents each battle presents unique challenges. Ever play a simple game of chess against the average computer program?
The problem is that they're following the paradigm of the "MMO" too closely and not borrowing from the hundreds of successful single player games which actually have decent gameplay. It's really not hard to imagine how the gameplay can be great if you don't limit yourself to comparing it to existing MMOs, which are notorious among critics for having incredibly lackluster gameplay design in contrast to single player games.
All that is not to mention things like changing classes. If nothing else, gameplay that is boring after 300 hours is much more desirable than gameplay that's boring after 30. If you don't even give your players an opportunity to get invested in their character, your game is doomed.
Ok, now we're going to get slash fiction of Wint x Kachi somehere... rule 34 and all...
Never confuse your inference as the listener for an implication of the speaker.
Good games are subjective like good food is subjective. You're not going to seriously tell me that there's not a psychological basis for why pizza is great and lutefisk is revolting. The thing about subjectivity is that, as subjects go, humans actually have a great deal in common.