Wut? You had me until the last paragraph. This is about being a jerk and not playing well with others. Frankly, that player would benefit from learning more about participation and maybe come to understand that playing a cooperative game isn’t about winning. Maybe if they’d received a participation ribbon or two they would have learned to value it more.
Playing well with others is a good thing. I think you misunderstand what participation ribbons are about.
Point taken. My diatribe took a turn at the end there and the two sections are somewhat distinct.
I acknowledge D&D is a coop game and not being a jerk is even more important in such game than in a competitive one (though sportsmanship is a desirable trait in all games, even competitive ones).
What I would say though, is that XP and treasure are the participation ribbons. It does not matter that one of the characters contributed less to a given encounter, they still get an equal share of the XP. And if their party aren’t jerks, they’ll get dibs on an item that is especially useful to their character (again, regardless of how much they contributed in the fight that yielded that treasure). This has been in the game as far back as I remember. In 2e there was a paragraph somewhere saying something along the lines of "the character who was guarding the exit and could therefore not participate in the combat may, unbeknownst to all but the DM, have discouraged monsters hidden in the other room from joining the fight, and in that way might have contributed more than all the others combined. So everyone shares the XP equally and you just don’t really know who actually contributed the most." I’m for sure butchering the text and the actual quote must be quite different but that was the essence of it as I recall.
Anyway, the point is, in my opinion, the game has had some sufficient amount of participation ribbons in its DNA since times immemorial, and I don’t think there is an imperative to perfectly balance every build in every fight to be equally effective. On average and in the aggregate, we want balance sure, but I am fine with the ups and downs of specific fights making a character shine and another bite their nails.
Here, would it have been an excessive participation ribbon to bend the rules at the insistence of that player? I thought so at first, but maybe there is a better concept (other than participation ribbons) to describe the situation, had the DM accepted. Would the player have behaved better and been less of a jerk if they had gotten more ribbons (of that kind or another) in the game and/or in their life? I honestly don’t know.