With the exception of the antennas designed with genetic algorithms[0], the "alien" aesthetic in all of these examples looks like the output of topological optimization tools. For example: https://www.youtube.com/watch?v=igRFFMSfwSQ

They emphasize that Dreamcatcher uses a "top-down" style of design, so maybe they are using deep learning for NLP to parse requirements and then feeding those requirements into normal topological optimization tools?

[0] https://ti.arc.nasa.gov/m/pub-archive/1244h/1244%20(Hornby).... (pictures from their post on page 5)