Alderaan, sorry. What creeped me out was the cavalier attitude-- Princess Leia watches her entire planet (think about what that means-- billions of people, children, animals, all the history, museums, photos and love letters in attics, on and on) blown to bits (and is subsequently tortured) and brushes it off like a flat tire.
But the destruction of an entire planet-- billions of people-- should be treated as a weighty matter, not a throwaway plot device (not in a franchise like Star Trek, anyway-- if you're dealing with something like, say, Lexx, it's a different matter).
In the case of both Alderaan and Vulcan the characters were still in the middle of a crisis and attempting to prevent the destruction of other planets.
Should Princess Leia have just sat down and cried, allowing the Rebel cause (and freedom throughout the galaxy) to be crushed on Yavin and letting Alderaan be destroyed for nothing? And who's to say that's not exactly what she was doing while she was trapped in her detention cell before Han and Luke showed up? But once there was a chance of escape, she was up and around and doing her job, because she's a good leader.
Should Kirk and Spock hold a memorial while Earth also was under immediate threat of destruction? How does that honor the Vulcans who died?
These weren't run-of-the-mill characters who had the option to grieve or ponder the horror of the situation at that moment, because they were responsible for protecting billions of lives. They had time to deal with the aftermath of the destruction of their respective planets when other planets weren't about to be destroyed too.
Also, I don't understand where you get the idea that these weren't treated as weighty matters just because the bulk of the grieving and eulogizing didn't take place onscreen. There was a gap in time between the end of the action and the respective awards ceremonies in each movie where a great deal of that could have taken place.
Was Spock's obvious despair in his after-action report about the destruction of his homeworld not satisfactory? Was his willingness to leave Starfleet to try and rebuild and repopulate his species not a sign of how very seriously he took the destruction of Vulcan? The characters were obviously devastated by what happened at Vulcan, but they had to set it aside temoprarily to do their jobs.
But in Star Wars and Buck Rogers these are parts of the original concept. In Star Trek, the original concept was a mission of exploration and discovery in an optimistic future, the sense of wonder married to an enlightened social attitude; this is a revisionist film that blows all that away in favor of explosions, surreal interpersonal violence, corrupted characters and general superficiality. Even putting aside the quality of the writing, that shows a terrible lack of artistic integrity.
The very first episode of Star Trek dealt with a species that had wiped out almost their entire civilization in a nuclear holocaust, and many more episodes and films dealt with that level of destruction or worse as well, usually as an allegory about our own tenuous peace and potential for nuclear destruction on Earth. War with other species was also part of the show right from the start. They're as much a part of Star Trek as they are in the other two examples, regardless of the coexisting themes of exploration and optimism.
Plus, your point seems contradictory in that you want the characters in Trek XI to show their profound suffering in the wake of the destruction of Vulcan yet also want it to be an optimistic tale of adventure and discovery. How do you do that in a two hour movie without relegating most of the grieving to offscreen or never doing anything that would make the characters emotionally devastated for a great deal of time?
I think the movie handled it perfectly. It acknowledged the grief at the destruction of Vulcan through Spock (and Uhura) but then moved on with the story by presenting an equally terrible threat to Earth before retouching on it toward the end. I don't see what else could have been done without making the whole movie a downer. If you're being reasonable in your judgment of the film it should be assumed that there's extensive grieving and memorializing going on offscreen. Not everything has to be spelled out in explicit detail.
[edited to add]:
His actions in the movie merit a court martial and being remanded to psychological treatment, not even counting the effect of the loss of Vulcan. Then think about how the witnesses to the 2001 terrorist attacks were effected mentally and emotionally. Now remember that the nu crew was not only witness to Vulcan being destroyed but tried to save them and failed. And most of these characters are kids. They are going to need treatment. Some would probably be on suicide watch. When they are eventually returned to duty, if they are, they would certainly not all be allowed to serve together.
Of course, that's not going to happen. It's going to be a Summer blockbuster.
Okay, to borrow your 9/11 example...
Do you think the pilots of the F-15s and F-16s on patrol over New York and Washington weren't as devastated by the destruction as the rest of us? What about the people at NORAD and military or civilian air traffic control centers? What about the President's staff and the President and VP themselves? Do you think they weren't feeling emotions? But that doesn't change the fact that they had a job to do and it was their duty to act responsibly and respond to the crisis at hand lest more attacks occur. The time for grieving is after the immediate crisis is resolved, and they did so when appropriate. The same happened in the film.
Your stretching because you didn't like the movie. Which is fine, but you shouldn't dismiss storytelling logic to make your point. The movie can't spend the entire time with people crying and still be a rousing adventure. At best you can touch on it in a poignant way before moving on with the main plot, which the film did in my opinion.
