difference in typecheck with 5.8 (intersection of types breaks some compatibility)

[dartess]

Same errors, locations, and messages as TS5.8

yet another little difference
(types are mostly copied from remeda)

type IterableContainer<T = unknown> = ReadonlyArray<T> | readonly [];
type Mapped<T extends IterableContainer, K> = {
  -readonly [P in keyof T]: K;
};
declare function pipe<A, B>(value: A, op1: (input: A) => B): B;
declare function map<T extends IterableContainer, U>(
  callbackfn: (value: T[number], index: number, data: T) => U,
): (data: T) => Mapped<T, U>;

type Point = { x?: number } & { y?: number };

export function update(modify?: (point: Point) => Point) {
  return pipe(
    [{ x: 0 }],
    modify
      ? map(modify)
      : map((point) => point),
  );
}

error TS2345: Argument of type '((data: { x: number; }[]) => { x: number; }[]) | ((data: { x: number; }[]) => Point[])' is not assignable to parameter of type '(input: { x: number; }[]) => { x: number; }[]'.
  Type '(data: { x: number; }[]) => Point[]' is not assignable to type '(input: { x: number; }[]) => { x: number; }[]'.
    Type 'Point[]' is not assignable to type '{ x: number; }[]'.
      Type 'Point' is not assignable to type '{ x: number; }'.
        Types of property 'x' are incompatible.
          Type 'number | undefined' is not assignable to type 'number'.
            Type 'undefined' is not assignable to type 'number'.

16     modify
       ~~~~~~
17       ? map(modify)
   ~~~~~~~~~~~~~~~~~~~
18       : map((point) => point),
   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

TS 5.8 is OK with that: playground

If we merge { x?: number } & { y?: number } as { x?: number; y?: number } the error disappears (but in my core I merge different types).