You now have to cast as THREE.BufferAttribute
E.g.,
// using array
const positions = (geometry.attributes.position as THREE.BufferAttribute).array
// using setXYZ
;(geometry.attributes.position as THREE.BufferAttribute).setXYZ(1, 2, 3, 4)
You now have to cast as THREE.BufferAttribute
E.g.,
// using array
const positions = (geometry.attributes.position as THREE.BufferAttribute).array
// using setXYZ
;(geometry.attributes.position as THREE.BufferAttribute).setXYZ(1, 2, 3, 4)