Is having a dead parent a movie cliché?

Overused plot device, not cliche.

I get the impression from listening to reviews of new Star Trek that they constantly have to have parents or ancestors of main characters who are also heroes or famous.

When I first saw the title of the thread I thought it said dead parrot

https://www.youtube.com/watch?v=t70338JIPY0

It's an old plot device that predates movies. Oliver Twist was an orphan and so was Jane Eyre. People like it. I always thought that it gave the underdogs in life someone to identify with. You might seem to be lowly Colin Commoner with nothing to look forward to but really you're wealthy Prince Peregrin Ponsonby with the world at your feet !

Yes! Especially in Disney films, where almost all of the young protagonists are short a mother, if not both parents.

It's done to give very young protagonists more freedom than the average child. Nobody can have adventures if they have a mother hovering over them, so the mother is usually just removed before the action begins,

It worked in "Psycho".

Yes, and a very overused cliche in novels too. The aim is usually to force the child into a situation where they in turn have to grow up or face some unknown adult conundrum, which makes up the meat of the entire novel/movie. Plus, it helps sell us on the obnoxious overt neglect of the remaining parent - since a lot of audiences often ask, where are the parents in this movie and why is parent X so negligent? Because they're in mourning, of course.

Idk why they don't just have parents be divorced, since that works just as well, but they don't always want to add that emotional baggage to the story, or they need to idealize the dead parent for some pay off or explanation for some action or event in the movie later, where the child realizes, hey, my mom/dad wasn't perfect after all.

I mean, it's a thing in comicbook culture too. Peter Parker's parents died. Bruce Wayne's parents died and that was in a 1938 comic. Then there's Superman whose biological parents and people were killed when his home planet exploded. So it's not just movies. It's in comics too.