Raiders' genius was that it understood that Indy had to be both unbelievable but also fully human. And since he was human you didn't really know how he was going to get out of each situation, and that tension drives the journey forward. But today, in movies like Crystal Skull, each situation breezes into the next. When Indy is trapped in a town set for nuclear detonation, he hides in a refrigerator. As the town is vaporized his refrigerator flies through the air, crashes to earth, rolls for half a mile, and Indy tumbles out and walks away.
This scene defines the movie in a nutshell. So over the top, so implausible, so strained, it has given rise to a new Internet phrase: Nuke the fridge. It's the moment when a movie or franchise goes to hell and never recovers. In this case it's the obliteration of the requisite cognitive dissonance needed for an Indy movie. Are the situations bigger? Definitely. But then the escapes must also be bigger and then beyond the realm of plausible deniability to the point where there's no reason to even worry. If Indy can escape a nuclear explosion in a refrigerator then it is mostly pointless to buy into his mortality just for the sake of faux suspense for the rest of the film.
The 1981 Indy was human. In 2008 he is invincible. In this, much of the magic and charm is lost. Here is a movie where anything can happen and does, even if it's laughable and irrelevant. Crystal Skull has all the earmarks of poor Lucas films: too much CGI, too much commenting through the obvious, not enough human touch. Or, to put it another way, not enough of what made a movie like Raiders so much fun.
I know people get upset by even comparing this movie to Raiders, as if they aren't even remotely related. And that's fair because they're not, really. This movie has far more in common with The Mummy or National Treasure 2 than it does with Raiders. But it's worth pointing out for this reason — it was made by the same people and by looking at one and the other it shows how far even its creators have sunk.