Theme games have this unfortunate tendency to get really, really long. That can contribute very much to the apathy. Sure, Large games in general are getting longer, but Large Themes hold the majority of length records for good reason. Players talk a lot more than they used to, and that can contribute very heavily to making you avoid the game. In short, themes are long, larges are long, and large themes compound the problem. It can be very difficult to stay invested when you have to read 20 pages a day. Alternatively, if the game slows to a crawl--and near-universally, every theme has this at a point, in mid-lategame usually--then one of the things required to get people out of the rut is to review the info...which requires trawling through long pieces of info to track down that single little thing you're looking for.
Also, in general, meta is more heavily featured in themes. Not just mod meta--player meta, too. Players in themes tend to, as noted, stick to themes. So that requires not only knowing them from the current game, but also from previous games...that are also themes with the same problem. In other queues, you don't deal nearly as much with the problem because you've got a constantly-rotating playerlist. (New people come in all the time, old people move out all the time.)
In short, there's just so much extra to keep track of, with it being a lot more effort. It's very hard to keep in the mindset of finishing the game pro-actively ("I want to win!") rather than passively ("I just want this miserable game to be over").
Generally one of the best things to do is to let go and accept your feelings for what they are, and to make the most of it. I try to have fun, and if I'm not having fun, I'm miserable, but I'll do what I can to use my state of being: I'll skim, I'll skip, I'll improvise, and be more creative with my play, since I've got little to lose and a lot to gain. If I keep having fun, then I keep having fun, and continue to do things that allow me to keep having fun, among them being that I won't take the game too seriously even if it appears like I am.
I'm not sure how much good that tip will do you, though.
Combating apathy is
a problem I still struggle with.