...I'm so happy that I write in untyped languages so I don't have to deal with any of this.

But you kind of do.

For a untype language like js array, since it can be empty, you have to either always check the length, the item returned, or have a precondition to know the array is not empty.

All three of those cases is either code or context you’re holding in your head.

All that stuff is equivalent to a type system

Congratulations on having to implement your checks at runtime, but stupid, repetitive, boring work is kind of why we invented compilers.