There are many ways to approach a generative patch, this is just one example. There's a few example generative patches in the factory sound set - filter by 'generative' type to find them.
(apologies for a couple of grammatical typos.)
Actually it's running on a 2018 i5 Mac Mini, not 2019 as mentioned in the video - although maybe those are the same processor for both years I don't know.
More info at :
https://www.hyperionsynth.com/
https://www.tracktion.com/products/hyperion
