There are a bunch of talking SEO pundits that spout their personal guesses and pass them off as real science. these guesses are too often bad advice bouncing around the SEO echo chamber. So how does someone find real scientific data?
You can use Google Scholar to search actual research papers & patents. I suggest you limit it to research no more than 2 or 3 years old since the internet landscape changes so much.
Google Scholar results for SEO [scholar.google.com]
Google Scholar results for Website Design [scholar.google.com]
You can also use [
sci-hub.cc...] to search and gain access to these scientific papers.
Happy researching!