Summary
Using AR Simulation to navigate the Samples Debug Menu scene, discovered planes and point clouds are obvious in Game view. In Scene view, discovered planes are obviously apparent but point clouds are not. In fact point clouds are also drawn in Scene view, you just really have to zoom in to be able to see them.
Per Alexandra, making the points bigger might not be the right answer as it might in turn make them too big on mobile and HMD, but she might be able to change the clipping behavior.
To See the Bug
Open the ARF Samples project in the Editor.
Open the Debug Menu scene.
In Build settings, select desktop platforms.
Enable XR Simulation in Project settings.
In Scene view, use the AR Simulation overlay to select the biggest office simulation environment.
Enter Play mode.
Click in Game view to give it focus. Then navigate in Game view using right-mouse + WASD. Note point clouds and discovered planes.
Click in Scene view to give it focus. Then navigate in Scene view using right-mouse + WASD. Planes that were discovered in Game view are readily aparrent, but to see the point clouds you need to get very close to the relevant surfaces. This is the bug.
Configuration
2021.3.0f1.2 (2021.3/staging 6eacc8284459)
MacOS 12.0.1, MacBook Pro (15-inch, 2019), 2.4 GHz 8-Core Intel Core i9
AR Foundation 5.0.0-pre.10 (f6569c5)