Why cannot use 'map or filter' in testing library with typescipt?

I cannot use to array method for testing library.

My test code is like below.

const ListTitle = fakeData.forEach((el) => {
      el.filter((element: string | object) => (typeof element === "string" ? element : element?.props?.children));   **** filter method has a error ts.2339
    });

Attached, I want to exclude only text in fakeData array.

fakeData is like below the code.

interface FakeDataProps {
  id:number
  titleChild:JSX.Element
}

const fakeData: FakeDataProps[] = [
  {
    id: 1,
    titleChild: (
      <>
        party goes on <span style=> The end</span>
      </>
    ),
  },
  {
    id: 2,
    titleChild: (
      <>
        party goes on <span style=>The end</span> Your time
        is ...{" "}
      </>
    ),
  },
  {
    id: 3,
    titleChild: (
      <>
        party goes on <span style=>The end</span>
      </>
    )
  }
];

I expected

[ "party goes on The end", "party goes on The end Your time is ...", "party goes on The end", ]

But, In my test code, There are error occured that has "Property 'filter' does not exist on type 'FakeDataProps'.ts(2339)"

What shall I do?