How have I not heard of this? Thanks for the pointer. I went a-googling and found Richard Bartle's paper. [0]
[0] https://www.researchgate.net/publication/247190693_Hearts_cl...
[0] https://www.researchgate.net/publication/247190693_Hearts_cl...
intro: https://www.youtube.com/watch?v=yxpW2ltDNow how a mixed ecosystem impacts things: https://www.youtube.com/watch?v=1drDuaQXm_U
https://en.wikipedia.org/wiki/Bartle_taxonomy_of_player_type...