I have to agree with a lot of what you said, which is why I mentioned it can be so tempting. I also do prefer solo jamming.
You mentioned learning, which is probably the most valuable reward out of any jam. While you do in fact learn a lot from facing challenges solo, you also can benefit greatly from your partner's experience. Not to mention that, should you decide to get into the game dev industry and work in a team, the lonewolf approach can only hinder your progress.
All of that aside, I honestly only join jams for the sheer fun of having to produce a game in such little time, and the satisfaction of seeing a baby game see the light. I wouldn't want to spend any of that time arguing with my partner which idea is better. Come to think of it, I did argue with myself.
Anyways, such a great game you have developed on your own! Congratulations.