Honestly, I'd take that as a major sign that this was not the right person for me- at least if this was at the potential stage.
If I got involved with someone, and he thought he could deal with poly, and really tried to work through the jealousy, but it was bothering him a lot, then I might be willing to take a break from other sexual involvements. If I was really deeply in love, AND my partner had issues with jealousy, AND he didn't have any interest in other people, AND I wasn't so deeply attached to someone else, then I might agree to monogamy, as long as it was re-negotiable if any of those factors changed.
I don't find it likely that will happen. There is one person who I think could meet all my needs, but even if by some weird happenings we ended up being in a relationship, he's a total slut and he's more likely to want to have all kinds of sexual adventures involving lots of other people than I am. He's not available, so I guess I've been assuming that the next major relationship I get into will be someone I'm settling for---and I would not be monogamous to someone I was settling for, even if there wasn't anyone else I was remotely interested in, I'd want to keep my options open.