There is no reason not to. And no, impostors are not a valid substitute for actual authored LODs, though they could be a decent pre-cull step; neither is distance culling. Relying on occlusion is also not an option, as layouts vary greatly, often not bringing camera close enough to targets.

We're currently stuck between two extremes: either you run on eleven-and-a-half vertices, or you rock LOD0 and effectively output microtriangles for anyone two or more meters away; more often than not it's the latter, and given commonly used fragment shader complexities (and their "quality") the performance impact grows exponentially. I guess this needs to be said: it's not 1996, and we can have more than 512 verts per scene. Especially in VR, where detail is paramount.

Previously stated excuses for not whitelisting the component were laughable at best. Just because few people will make use of it doesn't mean no-one should be able to use it. Safety system accommodates for LOD meshes under the mesh visibility umbrella.

Existing solutions rely on safety system allowing animator evals, as well as relying on contact receivers. It is janky, unreliable, and takes too much time to set up.

There is no need for implementing some magical automatic LOD generator either. Most automatic generators tend to mangle topology and related attributes beyond reasonable level even for flatscreen. If an author doesn't want to properly author LOD meshes, they can choose to use existing automatic generators themselves.