Unity custom camera projection only working in scene editor

I've found this article on Gamasutra on a custom camera projection to make 3D look more 2D and decided to implement it to make some gameplay tests.

I had to make some changes to make it work on URP(on unity 2019.3.6f1) but it "worked" with the following code:

using UnityEngine;
using System.Collections;
using UnityEngine.Rendering;
 
// This script is meant to be attached to your main camera.
// If you want to use it on more than one camera at a time, it will require
// modifcations due to the Camera.on* delegates in OnEnable()/OnDisable().
 
[ExecuteInEditMode]
public class CustomProjectionTest : MonoBehaviour {
    private void OnEnable(){
        RenderPipelineManager.beginFrameRendering += ScenePreCull;
        RenderPipelineManager.endFrameRendering += ScenePostRender;
        //Camera.onPreCull += ScenePreCull;
    }
 
    private void OnDisable(){
        RenderPipelineManager.beginFrameRendering -= ScenePreCull;
        RenderPipelineManager.endFrameRendering -= ScenePostRender;
 
        GetComponent<Camera>().ResetWorldToCameraMatrix();
    }
 
    private void ScenePreCull(ScriptableRenderContext context, Camera[] cam){
        // If the camera is the scene view camera, call our OnPreCull() event method for it.
        OnPreCull();
    }
 
    private void ScenePostRender(ScriptableRenderContext context, Camera[] cam){
        // Unity's gizmos don't like it when you change the worldToCameraMatrix.
        // The workaround is to reset it after rendering.
        
        foreach(var camm in cam)
            camm.ResetWorldToCameraMatrix();
    }
 
    private Camera _cam;
    private void Start(){
        _cam = GetComponent<Camera>();
 
        // Set the camera this script is attached to to use orthographic sorting order.
        // Instead of using the euclidean distance from the camera, objects will be sorted based on their depth into the scene.
        _cam.transparencySortMode = TransparencySortMode.Orthographic;
    }
 
    public Vector4 up = new Vector4(0, 1, 0, 0);
 
    // This is a Unity callback and is the ideal place to set the worldToCameraMatrix.
    private void OnPreCull(){
        var cam = !Application.isPlaying? Camera.current : _cam;
 
        // First calculate the regular worldToCameraMatrix.
        // Start with transform.worldToLocalMatrix.
        var m = cam.transform.worldToLocalMatrix;
 
        // Then, since Unity uses OpenGL's view matrix conventions we have to flip the output z-value.
        m.SetRow(2, -m.GetRow(2));
 
        // Now for the custom projection.
        // Set the world's up vector to always align with the camera's up vector.
        // Add a small amount of the original up vector to ensure the matrix will be invertible.
        m.SetColumn(2, 1e-3f*m.GetColumn(2) - up);
 
        cam.worldToCameraMatrix = m;
    }
 
    public static Matrix4x4 ScreenToWorldMatrix(Camera cam){
        // Make a matrix that converts from screen coordinates to clip coordinates.
        var rect = cam.pixelRect;
        var viewportMatrix = Matrix4x4.Ortho(rect.xMin, rect.xMax, rect.yMin, rect.yMax, -1, 1);
 
        // The camera's view-projection matrix converts from world coordinates to clip coordinates.
        var vpMatrix = cam.projectionMatrix*cam.worldToCameraMatrix;
 
        // Setting column 2 (z-axis) to identity makes the matrix ignore the z-axis.
        // Instead you get the value on the xy plane.
        vpMatrix.SetColumn(2, new Vector4(0, 0, 1, 0));
 
        // Going from right to left:
        // convert screen coords to clip coords, then clip coords to world coords.
        return vpMatrix.inverse*viewportMatrix;
    }
 
    public Vector2 ScreenToWorldPoint(Vector2 point){
        return ScreenToWorldMatrix(_cam).MultiplyPoint(point);
    }
 
    private void Update(){
        if(Input.GetMouseButtonUp(0)){
            Debug.Log(ScreenToWorldPoint(Input.mousePosition));
        }
    }
}

Well, kinda. For some reason, it only works in the scene editor, but not in the game. I just have no clue why

With Scene Editor:

In Game