This is very disappointing to hear. I don't feel that seasonal content has improved any MMO I've played and in some cases (especially World of Warcraft... WAR to a lesser extent) really took you out of the world and made you realize that you were actually playing a game. Seasonal decorations for player housing is something that can be avoided (and I have no say - if people want "Christmas lights" in December on their house, that's their house and their business) by players who don't wish to participate, but I'm not in favor of changing capital cities and other locales for seasons based on times of year that are based in our world (WildStar shouldn't have a holiday in December just because we do).
It is your game Carbine, and you certainly have the license to try holidays... and maybe they won't suck.
But they haven't added anything measurable to any MMO yet and I don't feel they'd be necessary or helpful in this one (never once during beta have I thought - this game is missing something.... ah, holidays!; that is very damning to the feature in my opinion).
Very disappointed. I was hoping that Carbine would be above this.
If I may present a (slightly biased) counterpoint and explanation...
Limited-time events in games are interesting because they change the state of the world for a while, giving players access to content that is only around for a brief time -- including some nifty rewards. This helps further spice up what may have become routine and keeps people around to check out what might change! Holidays are often used as a vehicle for this because they are, by their very nature, repeatable annually. As a result, all of the initial art and design work you've done for the holiday doesn't go to waste, because it will cycle back around. The same is untrue of a one-time event, where much of what you've done often gets discarded. In addition, by keeping them going annually, now players have something to look forward to coming back around. Maybe they really enjoyed the content, or missed a reward that they wanted to grab the previous year.
So now that we understand the vehicle of the limited-time content, why holidays around real-world holidays? It depends on the holiday, actually -- right now we're shooting for one per season. In American culture (I know it's different abroad, particularly for Halloween), Halloween and Christmas are two of the most prominent holidays in terms of decoration and mood. Outside of the game, people are more likely to be in the spirit of the holiday. Thus it's great to harness the broad strokes of that general holiday -- the spookiness of Halloween, for example -- without straight-up making the holiday itself in the game. It works far better than making a holiday that is very discordant with the real-world happenings.
In addition to all that, in certain times of year (Winter, Spring, Summer) there are weeks scheduled around the real-world holidays wherein many people have extra vacation time to indulge in their entertainment pastimes, like a li'l MMO they might play. Lining up the in-game holidays -- regardless of how relevant they are to the real holidays -- to be roughly around the same time leads to a good deal more novelty and interest.
Now, all that said, our goal with seasonal content is to change up the world a bit, provide some fun limited-time content you can look forward to cycling back once a year, and help make the world of Nexus more alive. That does not mean cramming Santa into Nexus' lore somehow, but instead to hit the high concept notes of a seasonal event with WildStar-flavored lore.
Holidays aren't for everyone, and I completely get that. But they're also content that's new and accessible to as many people as we can manage, and they tend to be pretty popular in my experience. I hope you'll give our take on the concept a try.