Any recent improvements in LOD generation technology?

I asked this last year. No good answers. The current situation seems to be that there are three choices for automated LOD generation - crappy open source code, really expensive systems such as Simplygon or Houdini, or tools tied to Unity or Unreal.

Houdini has the kind of LOD generation where geometry detail in higher LODs is baked into textures and normals of lower LODs. That lets you push mesh reduction much harder. You only need enough tris to maintain the outline at the lower LODs.

But Houdini is very expensive ($4000/yr/seat) and not suitable for embedding into something else. Is there any open source code that does that geometry-to-normals transformation?

With all the progress in AI-based image manipulation, there ought to be some LOD progress from that technology. Anything?