Trying to adjust parameters of MeshReflectorMaterial

I want to achieve the effect as seen in here, where it’s more blurred the farther away from the object:

I’m trying to adjust blur falloff in this project: GitHub - 0beqz/vanilla-threejs-meshreflectormaterial-example: Vanilla three.js MeshReflectorMaterial implementation. All credits for the original implementation go to:
which is a ported vanilla of the MeshReflectorMaterial

my changes in this ported project are:

plane.material = new MeshReflectorMaterial(renderer, camera, scene, plane, {
resolution: 1024,
blur: [10000, 800],
mixBlur: 2.5,
mixContrast: 1.5,
mirror: 1,
maxDepthThreshold: 1.4,
depthScale: 0.1

// plane.material.setValues({
// roughnessMap: new THREE.TextureLoader().load(“/roughness.jpg”),
// normalMap: new THREE.TextureLoader().load(“/normal.png”),
// normalScale: new THREE.Vector2(0.3, 0.3)
// })

but all I get is a darker floor and no blur falloff:

does anybody know how to fix this?
thanks in advance!