Why do some types of storyline/genre get remade over and over again with little difference, while others remain standalone?

There are other movies like the Truman Show - Real Life, EdTV, Stranger than Fiction, Synecdoche New York all come to mind - but it's not a versatile concept where you can just use it for multiple storylines. "Technology goes wrong" gives you a lot more flexibility to apply the concept in different way. In fact, you could put Truman Show in the "technology gone wrong" genre. It's basically "Dystopian Surveillance State" meets "Technology Gone Wrong."

I've seen some people saying that Free Guy was too similar to Truman Show

OP, here are a couple of inspirations for **The Truman Show**: **The Secret Cinema**: https://www.imdb.com/title/tt0156056/ **Iceman**: https://www.imdb.com/title/tt0087452/

Because of the increasing spend amount required to make a film they try their best to ensure it'll e a success and developing a formula / repeatable plan often comes across to the viewer as tropes / repeated storylines. It usually takes an independent film producer to do something new or c**** for them to gamble on changes or positions where they are or have made lost of money and the later is far from true recently so you can expect them to stick with what they think are formulas for success

An episode of the original Twilight Zone is similar to The Truman Show “The After Hours” - the main character slowly realizes she is a mannequin come to life temporarily

Hollywood does this a lot. They see a popular movie, pick out one detail they think was the linchpin, and crank out more movies with that detail added. After the Matrix, black leather was common for scifi (and X-Men). After Guardians of the Galaxy, it was the 70s music. We have a trope called "Die Hard on an X" because... well, you get the point. Jaws, 28 Days Later/Dawn of the Dead (2004), Raiders of the Lost Ark, the MCU, Scary Movie, Bourne Identity, Animal House, Alice in Wonderland (2010), Gremlins, and Avatar are just some of the movies that started trends to copy some aspect of a hit and hoping to make a success. A lot of those trends tended to run for a decade or less before studios rubbed two brain cells together and moved on; that doesn't mean we don't still get those movies, but it does mean you aren't getting 8 knockoffs over the next 4 years anymore. There are only 7 basic plots in literature. There are 10 basic plots in filmmaking (detailed in the book ***Save the Cat! The Last Book on Screenwriting You'll Ever Need)***. There are 7 basic plot points in storytelling. Stories need a minimum of three acts. At some point, it's unavoidable that a work will be compared to an older work. Sometimes it comes down to "if it ain't broke" or "great minds think alike". Sometimes it's just someone deciding things could've gone different if X happened so they wrote a similar story to set up their version.

Free Guy took a lot of inspiration from Truman Show and that was made in 2021

Ones are susscesful. Others not.