Why does this simple foreign key one-to-many relationship give Typescript errors ?

CREATE TABLE public.playlists (
    id bigint generated by default as identity primary key,
    track_id bigint references public.tracks NOT NULL
);
CREATE TABLE public.tracks (
    id bigint generated by default as identity primary key,
    title text NOT NULL,
    artist_name text
);

const { data } = await supabase
  .from('playlists')
  .select(`
    id,
    tracks (
      title,
      artist_name
    )
  `)

Property 'title' does not exist on type '({ title: string; } & { artist_name: string | null; }) | ({ title: string; } & { artist_name: string | null; })[]'.
Property 'title' does not exist on type '({ title: string; } & { artist_name: string | null; })[]'.