There are too many movies, and not enough differentiation between them; everything ends up blending into one generic action movie with lots of explosions, dramatic music, and uplifting finales that may or may not have been earned by everything that came before. It’s not simply that we, as an audience, have grown weary of all of the manufactured “excitement.”
Here's a theory: maybe it is that simple. Maybe we have grown weary of manufactured excitement, emphasis on that first word: manufactured. And maybe the problem is that we've introjected this manufacturing process and confused it with real creativity.
The reason there are "too many movies and not enough differentiation between them" is because of the way they're put together from a template that has been ruthlessly purged of any possibility of deviation from a standard formula. The guys who have "cracked story", as Michael Tolkin put it, have made sure of that. They've trained Hollywood, from readers on up to producers, to look for nothing but stories of that kind in the first place, to sell nothing but stories of that kind, to condition audiences to expect nothing but stories of that kind, and to train the next generation of creators to produce nothing but stories of that kind.
A concession. I'd be courting hypocrisy if I said I didn't enjoy some of the product spat out of this machine. I liked Man of Steel far more than I thought I would, but I suspect any property that has much of an emotional aura to it is going to inspire that much more attention to get it right. When there isn't as much native emotion involved — Iron Man 3, for instance — the results are correspondingly bland, and all the "emotions" are just synthetic plot beats in disguise. (IM3 in particular annoyed me, because it treated at least three of its own major emotional ingredients with butterfingered incompetence.)
A story isn't an emotional experience just because it contains ingredients that we commonly associate with having an emotional experience. A story can contain a death, an illness, a ruined life, etc. without actually being about any of those things, and will seem correspondingly all the more empty for having done so. Imagine a mealtime conversation partner who babbles on endlessly about everything that happened in his life but never seems to actually care about any of it.
The more we pump our entertainments full of things that are just referenced or included without being felt or understood, the emptier it all gets. I don't know if the delivery mechanisms we've settled on are part of the problem, but I'm fairly sure they don't help.
Wasn't it your mom who originally said, "You can't force yourself to have a good time"? As usual, Mom was right.