The FACT that they narrowed an HISTORIC EVENT to TWO WEEKS, is NOVEL. Feels familiar and I DO NOT LIKE IT.
If you're talking about the Treasure of Crystal Cove length this year, then it's almost always been
shorter than two weeks. If you look at the wiki (other than a typo when it apparently ran from August 2016 to August 2017, which I can guarantee you was not the case) it usually runs give or take eleven days, sometimes even less.
There are some exceptions, like 2022 where it ran much longer than normal, but in 2020 for example it ran for a shorter window than average. I'd say this year's Crystal Cove is basically the same window as most years, though some years did get a nice double dip which I wouldn't mind. It seems like DDO's events are kind of too rare, and I wouldn't mind occasionally having one during the summer break even if there's nothing new, just to have something to shake up a life or two once in a while. Having an occasional "event weekend" before a big patch or during a lull in the release cycle could be a good way to relieve some of the event FOMO and give more players the chance to participate if they get real life'd out of the original window.
It is a little odd how many events are co-located this year, with the new event, Night Revels, and Crystal Cove all starting September-October, but it's not like any of them are irregular compared to historical event length. This is roughly the same way DDO has run events- Crystal Cove in August/September, Mabar/Night Revels runs through the better part of October and sometimes a bit of November, and then hardcore seasons (or lanterns of the mist as an inheritor of that tradition) seeming to pick up more or less at random. They just happen to be very close in scheduling, which is novel, not the length of any of them.