Many of the videos and studies are very interesting and I’ve bookmarked to review in detail more. Local UI patterns in particular, however there is a lot of guesswork.

I feel like this article is missing many crucial pieces of the puzzle, the biggest one these is: accessibility.

Some markets do not have the laws to factor in disabled users into the technology. As a result these users can often be ignored. In the UK this can be as high as 22% of the population.

The studies you cited, when I searched for disability or disabled as a keyword nothing came up. It's unclear if these users were included in the testing of the studies you cite.

Should a product or service not have to consider these people this concept of "preferring complex UI" falls by the way-side. There are also seemingly many aspects about culture that have been extrapolated into UX design that is very hard to review.