First off, most of them are trash. They are “in book” and are the hallmarks of anime, but people still watch them. They all have a similar main character that got thrown into another world and often have some insane, overpowered skill. Over and over people still watch them trying to get another one that has “the novelty,” something that spices it up and does something different, but if it isn’t to their satisfaction then they call it trash. Of course some Isekai anime are complete trash, with names that consist of an object, level 999, and Op in the title. It’s like a click baited Youtube video, but as a show or book. The whole genre has gone into a slice of life with barely any action or risk for the character. If you were to take a handful of them and look at the main character, you would probably find a brown haired boy with the standard Mii haircut.

Standard Mii Haircut

Sometimes they dye their hair, but eventually it’s all been seen, most of them are “in book” characters. But, in the end, people still watch it and read it. They still like seeing it and use it as a buffer between episodes or chapters where a character dies, or when it ends.

In itself, the genre is a novelty (some of it), something that isn’t heavy, or sad, or realistic, it’s just there. People are used to seeing books and shows that are gory, sad, or just realistic, but when you have a genre that’s just outright breaking the laws that they put into their own story, it makes people laugh, or hate it. It’s a novelty in the world of stories, even if it’s used over and over. It’s an amalgamate of genres, but if they were taken as something silly. It’s silly seeing hate on something that isn’t supposed to be taken so seriously. If it was supposed to be serious then it would be noticeable. They would have characters that had flaws and morals that might conflict with others and the fights would have a reason. There’s quite a few of them that make themselves serious, but they still include the silliness of the rest of the Genre. 

The Genre may be considered drained out and trash, but it’s not supposed to be taken seriously. It being trash, recyclable trash, is what makes it unique and special. Some of it is actual trash, but in general, it’s silly. The best jokes are the ones that still have people telling them even if people know what it is. This is what makes the Isekai genre unique and a novelty.