Speed Racer might be an exception to that. My Target store has two end-caps plus a big chunk in the die-cast car aisle.
I agree, though, that some movie lines are being cut back. If you look at The Golden Compass or Prince Caspian, the lines aren't that big. But honestly, do you remember how much crap came out for films in the past? Godzilla, Men In Black, Independence Day, Planet of the Apes? Hell, Spider-Man 2?
Stores were flooded and got stuck with a lot of stuff, especially TRU on the first 4 examples I listed. You could still find Godzilla stuff at TRU stores 5+ years later, PotA 4 years later... Since then it seems like lines have been smaller over all and I'm in favor of that.
Not every film that hits needs a toy line but some lend themselves better than others. Speed Racer actually does lend itself to toys with all the different race cars and such, but Iron Man is one guy with a couple different suits. So can Hasbro really build a huge line around that? Toy Biz tried, and IMO, failed miserably with Spider-Man 2. For months there were HUGE aisles at WM and TRU filled with nothing but Spider-Man and then, finally, one or two Doc Ock figures trickled out. The SM 3 line was smaller and Hasbro made sure that there were other villains on the shelf at the same time. At launch you weren't stuck with just SM and Sandman, you could also get Rhino or Doc Ock or even Goblin figures as well.
You mentioned the Narnia series and I'm not actually sure that's the type of film that lends itself to figures but I do, in fact, really like the looks of some of the beast characters that are out now. The Golden Compass? Not really an action figure type of film and that line seems to have generally tanked.
Pirates was big when it first launched and I think there was potential for more from that toy line if the original film had hit with a trilogy in mind, the action figures had been out to cover all three films and if the third film hadn't sucked.
If I look at the movies coming out this year, the ones that lend themselves to toy lines seem to be Batman, Iron Man, Speed Racer, Indiana Jones, Hulk, and Wall-E. The three comic book films need smaller lines because you're really talking one hero, one villain and a handful of, probably, rather boring everyday people. Speed Racer has the benefit of the cars, Wall-E has the benefit of being a Disney movie with a bunch of cute background characters and Indy has 3 films already in the can to draw from.
Harry Potter is actually an odd one. I'd have thought that that set of films could have huge potential for figures. The original lines seemed to do okay from what I saw, but then they switched up the scale for Prisoner of Azkaban and it kind of died. The new Neca stuff is neat but expensive and limited to collectors. That set of films lends itself to small playsets and accessories and I think would have been a brilliant choice for 3.75" scale. Could you imagine fielding whole Quidditch teams? Getting Dark Arts and Potions classroom dios? The Gryffindor Common room? Don't get me started...I'd almost give up SW collecting for that. I just think that the goals for that line got messed up somewhere and never recovered.
One of the things Star Wars has going for it, besides hugely popular movies and 30 years of nostalgia, is the depth of the pool to draw characters from. A background character from Spider-Man looks like me sitting at a cafe. A background character from Star Wars looks like Greedo. Which would you rather buy a figure of? Bruce Wayne rides around in a limo, Han Solo flies the Millennium Falcon past black holes... See where I'm going with this? Not all of the big hits have big, cool characters and "stuff" to choose from and those films don't need big toy lines. I think retail and license holders are finally starting to realize that.