I don't think we can say much about the natural state of people nor the logical state, and even if poly was we're humans who arent bound by natural or logical state.
I can appreciate monogamy as default as being harmful, I think its a bit overwrought to say that but I get it. As the hegemonic default, a lot is negotiated and more or less thats because people know the script for it - don't cheat on your partner, but what cheating means can be stretchy and culturally coded. Some people think an emotional affair and a smooch is serious, some think it only crosses the line with sex, whatever. That could use some negotiating and communication - but also, dont cheat on your monogamous partner and if you cant, then dont partner uo monogamously. I dont get the harm in 2026 where you cant just sow your wild oats as a single person but everyones making you be monogamous with a partner except you also wanna still hit on other people? That part feels very overwrought. I could definitely see monogamy as an institution be historically harmful and oppressive but get real for today in the hegemonic society - you dont need to be paired up.
I still dont think its a kink nor invasive, I think thats still very silly framing. Its a kink as much as poly is (to me, not at all). Its just a way people have relationships.
