Aren’t those extremely high notes for voices in those classifications?

They shouldn’t be if the larynx stays resting in a relaxed, stable speech-level position, allowing your vocal cords to adjust freely with your breath flow. Those pitches are well within the technical ability of a great many more people than you’d think. They may not sustain those notes constantly, but they should be able to sing them with good technique. This way they will always have a reserve of notes beyond the usual range requirements of any song they sing.