
Then just don't read them? I don't see why you have to be frustrated over the inevitable. There can only be more works created, not less. Nothing in this world is original anymore. And eventually nothing will ever be original anymore. We just go through cycles of genre popularity and that's it.
If you feel so bored and disgusted with it all, try writing your own (non-offensively intended).

As someone who’s read both, they’re different takes of the same very basic concept lol, that’s like saying all mangas about acting or zombie mangas are copying each other and have no originality. The authors both contribute something to this concept (frankly a great one) and if ud bothered to read then maybe u would know that ¯_(ツ)_/¯

If you are so frustrated, then you could create your own story?! It's called a Genre for nothing. So of course it might have similarities. Especially when they have to create an adaptation of a novel. There might be others who would create their own adaptation. It's same to movies & series too. There would always be similarities. I would like to see how you can come up with a story without any similarities?

If you are bored of a genre, then I suggest you to stop reading at all. Go play some sport or go hiking or something more adventurous. No watching movies & no playing games either. Because there would always be repetition of something that can make you disgusted, thinking they copied each other ┑( ̄Д  ̄)┍
Funny how we had a horror game Isekai trope and now this copied it these author's can't have their own originality.. OMG