Definitely, not all people desire more than one person, but those people are exceedingly rare. Most people do.
We will have to agree to disagree on this one! Saying that "most people" want to have romantic relationships or sexual relationships just seems like another way of saying polyamory is more natural and that it works for most people, neither of which I think are true.
The fact that infidelity and poly-sex/poly-amory are so common stand as testaments to that. If we were to consider infidelity as a different form of poly-relationships (the unwitting poly participant), it’s safe to say that almost everyone is some form of poly dynamic, whether they know it, or agree with it, or not.
So... you're saying that in monogamous relationships, almost everyone cheats? I definitely don't agree with that. There are LOTS of people who are happy in monogamous relationships and don't cheat. Beyond that there are lots of people who aren't totally happy and still don't cheat. I also do not think polyamory is as common as you're making it out to be at all.
I also don't think categorizing infedelity as a type of polyamory really does any service to anyone.
Further compounding the problem are things like retroactive jealousy, where partners are faithful together, but one partner feels extreme bouts of jealousy about the past partners of another — the fact is, even most monogamous people will develop multiple romantic connections throughout their lives, just not at the same time, and some partners will become quite upset over this fact. Finding someone who’s waited for marriage, never felt attraction for anyone outside of their one, lone, singular spouse, and never had any desire for any additional connections that they might try to realize, seems an abysmally difficult task.
I don't know that I really follow this line of thinking. I don't think most people expect their monogamous partner to never have had other partners. Yes, some people get jealous, but jealousy is actually a function of other deeper feelings, whether they are feelings of insecurity or loneliness or having needs that are not being met. I don't think that equating polyamorous relationships with having had multiple non-overlappiny romantic relationships is accurate. It's comparing apples to oranges. Having had multiple monogamous relationships and being happy in them isn't the same thing as having multiple simultaneous poly relationships and being happy. It's a false equivalency.
Personally, I have someone I’m happy with and need nothing more. I’ve had a lot of quality experiences with great people and I’m settled, so I’m committed and have learned to be happy with what I have…but I also realize how few people are able to do this, and I only can because of a lengthy sexual history — I already know what’s out there waiting for me, so I know that what I have is the best choice for me.
I think it is very cynical to assume that so many people are unhappy and unfulfilled. It is great you have found something that works for you, but I don’t understand how you can both tout polyamory as being the end all be all and say that you have settled for being monogamous and learned to be okay with it. That seems to be the very example that what works for people works for them, yet you still are insisting that one thing is more natural.