These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Indiana Jones And The Kingdom Of The Crystal Skull
Broken Base: Reviewers, fans, casual viewers, all possible groups are split!
Hate Dumb: Many of the haters seem to have made up their minds to hate it before they even knew what it was about, solely because it was new and came after two widely-loathed films that sullied George Lucas' reputation.
The episode was ambiguous over whether the message was played straight or was a parody of the Fan Dumb, however, considering that Butters, quite often the voice of reason whenever he has a significant role, liked what he saw but was ignored by the rest of the townsfolk.
Then again, most "hardcore" fans hated it for the inclusion of aliens and the "nuking the fridge" scene.
Inferred Holocaust: The tribe that lived near the temple most likely were killed by the departing spacescraft or drowned by the river flooding the valley.
At least, any who remained after the Russians gunned down all the tribesmen who were guarding the temple, as shown on-screen.
Jumping the Shark: Many fans thought the "nuking the fridge" scene was this. It's telling that there was an attempt to make "Nuke the Fridge" a movie-equivalent trope, even though the term "Jump the Shark" was coined years after the ensuing incident on Happy Days, not days.
The original 1982 Back to the Future script featured Marty McFly surviving a nuclear blast in a fridge-time machine, in order to return to the present. This was scrapped in rewrites simply because it was too expensive to pull off, and there were concerns that kids who watched the movie might climb into abandoned refrigerators to "play Marty." If that sounds at all familiar, it's because Spielberg was also executive producer of that film, and also used the idea in an earlier version of the script in the earlier years of the franchise that was later adapted into this movie.
One True Pairing: There is one aspect of this movie about which pretty much everyone can agree, and that is that Karen Allen's return as Marion Ravenwood is FUCKING AWESOME.
In fact, practically every brand new character introduced in Crystal Skull is hated for little reason beyond being in Crystal Skull.
Special Effect Failure: The prairie dogs and the monkeys have been derided for this. The chase scene in the final act utilizes a good deal of green screen.
They Changed It, Now It Sucks: A common complaint of it's disappointed viewers. Some long term fans criticized the heavy emphasis on CGI for many of it's action set pieces (and in general) when the original trilogy was famous for its now iconic stunt work and great use of practical effects alongside CGI. Others feel the shift away from supernatural/fantasy elements towards sci-fi and aliens was a move too far.