There was some work ongoing to move to Lua internally and gradually move over to it, but it's a huge task and I've not kept up on recent progress with this.

This would of course be a huge improvement, but there are many details to get right to support the old and new scripts in parallel to effect a smooth transition. But in the long term, this will resolve many complaints about CMake and really improve the semantics of the language and development and debugging of scripts.