Greetings, programs! With the MCDM community's help, I've prepared a survey of GM styles, so that I can use factor analysis to find the common variables underlying GMs' responses, and come up with a scientific answer to "what kinds of GM styles are there?" The survey has 43 questions and takes a few minutes to complete. The more people answer, the better the data we'll get.
EDIT: We got 101 responses and now we're analysing the data. First results: There are 9 dimensions of GM style! Not sure what they are, but there's 9 of them.
Kudos for mentioning Everyone is John.
And since I’m already typing a reply, I might as well link to another obscure RPG (that I haven’t played):
https://rpggeek.com/rpg/104103/boss-dragons-and-scrambled-eggs