Variety has a bunch of short essays about the problems in Hollywood, but two executives discuss the commonly-held sentiment that there are just too many sequels coming out of Hollywood.
Jim Gianopulos, chairman and CEO of Fox Filmed Entertainment defends the choice to make more movies in a series, so long as they're good:
If you do sequels badly, that's the problem. I think the risk in sequels is for Hollywood to take the audiences for granted, to assume you only have to give them a little more. We as a studio are very careful to avoid that. We do that by introducing new filmmaker voices. We have to work hard to constantly advance the mythology of a property that people love. If you bring all the elements together, you'll succeed.
The other person addressing the reliance of Hollywood studios on franchises was Walt Disney Chairman Alan Horn, who said that film economics have made it very hard to make movies on a small budget. And tentpole franchises can actually make a profit:
I've long been a believer in the power of tentpoles to drive our business, but there's a special place in my heart for smart, emotional films on a smaller scale. I think that's true for all of us who love movies. Great stories come in all sizes, but the economics of the business have made it increasingly difficult for smaller movies to be profitable and, in turn, to get made. Audiences have so many things competing for their time and attention that just having a good movie with big stars from a reputable studio isn't enough anymore; it's extremely difficult to break through the noise.
Interestingly, Gianopolus pointed out that investment in making sequels bigger has paid off for them:
We gave "X-Men" and "Planet of the Apes" substantial budgets to allow the filmmakers the creative freedom to realize their vision. In the case of "X-Men," we were reuniting two sets of "X-Men" casts from "First Class" and from the earlier films. The nature of the story and the number of characters required a bigger budget. "Dawn of the Planet of the Apes" was told from the perspective of the apes, so it required more apes. The critical response and the audience response were greater than the fanbase prior to the movie. That's the other benefit of a sequel: It will introduce a new audience that may have been aware of prior movies but hadn't connected to them.
Even small films are expensive, and the ones that turn a profit need bigger and bigger investments to produce good sequels. Horn says that it's on the studios to figure out a way around this problem, to bring production and marketing costs down while also giving word of mouth time to grow. On that last point, he's absolutely correct. The emphasis on opening weekend grosses is horrible for smaller films. And it ignores the films that fall off the top ten really fast due to poor word of mouth — films that should maybe not be considered successes simply because they opened big.