Fantastic post Tom! There's a lot of confusion on direct traffic to begin with. These are even more finer nuances that you have explained. I have a client whose top source of traffic is direct, and part of it is maybe due to the fact that they don't do any promotion, and it's mostly shared around internally within their team. But I just noticed that their URL is http and not https so this might be something for me to take back to the team. Thanks!
The term “organic traffic” is used for referring to the visitors that land on your website as a result of unpaid (“organic”) search results. Organic traffic is the opposite of paid traffic, which defines the visits generated by paid ads. Visitors who are considered organic find your website after using a search engine like Google or Bing, so they are not “referred” by any other website.