In my opinion, monogamy is largely a patriarchal structure. If couples choose to engage in that because it’s truly what they want and it works for them, then please be my guest, but mostly I think that it’s just SO socially enforced that most people don’t realize there is anything else available to them. Being non-monogomous means you have to learn good communication skills and good boundaries and healthy non-codependent ways of being with other people. Not everybody is up for self-reflection and learning to deal with their shit and would rather just run around on their partners behind their backs or become stifled in relationships that still have love but no more spark. Too bad for them, because the work is worth the payoff.
Good for you for living life out loud!