I replied on that poll, but hadn’t notice you had posted it.
I think maybe what you mean by “majoritarianism” is what I want, but that is not the word I’d use. I don’t think the concept of “majority” is meaningful in a context when there are more than two candidates.
I think I want the term “game theoretical stability.” (let’s abbreviate it “GTS”) GTS vs. utilitarianism is kind of the difference between a Condorcet method (especially “aggressively Condorcet” methods like Stella-Toby: Does this sequential variation of STAR exist? ) and plain old Score.
I have regularly used an analogous voting concept to represent this concept (median vs. average when voting for a numerical value: https://pianop.ly/voting/median.html ), but a few days ago @cfrank reminded me of Vickrey auctions (sells to the highest bidder at the 2nd highest bid value) and how they compare to Dutch auctions (sells to the highest bidder at the highest bid value). Same thing. While it isn’t voting per se, Vickrey is GTS, Dutch is not. It is very much analogous.
Almost everyone new to the subject likes the non-GTS ones because they seem more intuitive. GTS methods seem to discard important info. We go round and round on this, but some people seem to understand this insight that dispensing with certain data, very explicitly and early in the process, is an absolute necessity. Otherwise it becomes a game of rock-paper-scissors, where you are trying to guess how other people will vote, and they are trying to guess how you will vote, ad infinitum. GTS methods (including with auctions, just replace the word “vote” with “bid”) don’t have this situation.
I don’t know of a term for it other than “GTS,” but I wish there was one that captured it better. Obviously it isn’t “majoritarian” because that word doesn’t apply to these very similar situations but where “majority” makes even less sense.
As for proportionality, I kind of wish that wasn’t in there. It doesn’t apply to single winner elections, and seems to go in with the assumption that there are discrete parties – as opposed to all voters lying on a multidimensional spectrum. I’m just not a party person.