array_walk_recursive changes variable type to incorrect

I have an array array<int, array<int, int>>, that I pass to array_walk_recursive.

The first parameter in the callback function int &$id I take by reference, then I change the value to a different type. (e.g.: string) Though I define the @param-out string $id annotation, the inferred type is not what it expected.

Expected: array<int, array<int, string>> Inferred: array<array-key, mixed>

https://psalm.dev/r/097021124e